diff --git a/src/swarm-engine/Swarm/Game/State/Initialize.hs b/src/swarm-engine/Swarm/Game/State/Initialize.hs
index ce968fe20..ff0816e03 100644
--- a/src/swarm-engine/Swarm/Game/State/Initialize.hs
+++ b/src/swarm-engine/Swarm/Game/State/Initialize.hs
@@ -1,3 +1,4 @@
+-- |
 -- SPDX-License-Identifier: BSD-3-Clause
 -- Description: Game-related state and utilities
 --
@@ -39,9 +40,11 @@ import Swarm.Game.Robot.Concrete
 import Swarm.Game.Scenario
 import Swarm.Game.Scenario.Objective (initCompletion)
 import Swarm.Game.Scenario.Status
+import Swarm.Game.Scenario.Topography.Cell (Cell, cellToEntity)
 import Swarm.Game.Scenario.Topography.Structure.Recognition
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Log
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Precompute
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Type
 import Swarm.Game.State
 import Swarm.Game.State.Landscape (mkLandscape)
@@ -177,19 +180,19 @@ pureScenarioToGameState scenario theSeed now toRun gsc =
 
 mkRecognizer ::
   (Has (State GameState) sig m) =>
-  StaticStructureInfo ->
-  m (StructureRecognizer StructureCells Entity)
+  StaticStructureInfo Cell ->
+  m (StructureRecognizer (Maybe Cell) Entity)
 mkRecognizer structInfo@(StaticStructureInfo structDefs _) = do
   foundIntact <- mapM (sequenceA . (id &&& ensureStructureIntact)) allPlaced
   let fs = populateStaticFoundStructures . map fst . filter snd $ foundIntact
   return
     $ StructureRecognizer
-      (mkAutomatons structDefs)
+      (mkAutomatons cellToEntity structDefs)
     $ RecognitionState
       fs
       [IntactStaticPlacement $ map mkLogEntry foundIntact]
  where
-  allPlaced = lookupStaticPlacements structInfo
+  allPlaced = lookupStaticPlacements cellToEntity structInfo
   mkLogEntry (x, intact) =
     IntactPlacementLog
       intact
@@ -201,7 +204,7 @@ mkRecognizer structInfo@(StaticStructureInfo structDefs _) = do
 -- cell is encountered.
 ensureStructureIntact ::
   (Has (State GameState) sig m) =>
-  FoundStructure StructureCells Entity ->
+  FoundStructure (Maybe Cell) Entity ->
   m Bool
 ensureStructureIntact (FoundStructure (StructureWithGrid _ _ grid) upperLeft) =
   allM outer $ zip [0 ..] grid
diff --git a/src/swarm-engine/Swarm/Game/State/Substate.hs b/src/swarm-engine/Swarm/Game/State/Substate.hs
index 4481fbd79..da4100a9b 100644
--- a/src/swarm-engine/Swarm/Game/State/Substate.hs
+++ b/src/swarm-engine/Swarm/Game/State/Substate.hs
@@ -101,8 +101,9 @@ import Swarm.Game.Recipe (
   outRecipeMap,
  )
 import Swarm.Game.Robot
-import Swarm.Game.Scenario (GameStateInputs (..), StructureCells)
+import Swarm.Game.Scenario (GameStateInputs (..))
 import Swarm.Game.Scenario.Objective
+import Swarm.Game.Scenario.Topography.Cell (Cell)
 import Swarm.Game.Scenario.Topography.Structure.Recognition
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Registry (emptyFoundStructures)
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Type (RecognizerAutomatons (..))
@@ -326,7 +327,7 @@ data Discovery = Discovery
   , _availableCommands :: Notifications Const
   , _knownEntities :: S.Set EntityName
   , _gameAchievements :: Map GameplayAchievement Attainment
-  , _structureRecognition :: StructureRecognizer StructureCells Entity
+  , _structureRecognition :: StructureRecognizer (Maybe Cell) Entity
   , _tagMembers :: Map Text (NonEmpty EntityName)
   }
 
@@ -349,7 +350,7 @@ knownEntities :: Lens' Discovery (S.Set EntityName)
 gameAchievements :: Lens' Discovery (Map GameplayAchievement Attainment)
 
 -- | Recognizer for robot-constructed structures
-structureRecognition :: Lens' Discovery (StructureRecognizer StructureCells Entity)
+structureRecognition :: Lens' Discovery (StructureRecognizer (Maybe Cell) Entity)
 
 -- | Map from tags to entities that possess that tag
 tagMembers :: Lens' Discovery (Map Text (NonEmpty EntityName))
diff --git a/src/swarm-scenario/Swarm/Game/Scenario.hs b/src/swarm-scenario/Swarm/Game/Scenario.hs
index ff94592b0..1f9c9d3d5 100644
--- a/src/swarm-scenario/Swarm/Game/Scenario.hs
+++ b/src/swarm-scenario/Swarm/Game/Scenario.hs
@@ -13,13 +13,9 @@
 -- conditions, which can be used both for building interactive
 -- tutorials and for standalone puzzles and scenarios.
 module Swarm.Game.Scenario (
-  -- * WorldDescription
-  StructureCells,
-
   -- * Scenario
   Scenario (..),
   ScenarioLandscape (..),
-  StaticStructureInfo (..),
   ScenarioMetadata (ScenarioMetadata),
   staticPlacements,
   structureDefs,
@@ -95,9 +91,10 @@ import Swarm.Game.Scenario.Topography.Navigation.Portal
 import Swarm.Game.Scenario.Topography.Navigation.Waypoint (Parentage (..))
 import Swarm.Game.Scenario.Topography.Structure qualified as Structure
 import Swarm.Game.Scenario.Topography.Structure.Assembly qualified as Assembly
+import Swarm.Game.Scenario.Topography.Structure.Named qualified as Structure
 import Swarm.Game.Scenario.Topography.Structure.Overlay
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Symmetry
-import Swarm.Game.Scenario.Topography.Structure.Recognition.Type (SymmetryAnnotatedGrid (..))
 import Swarm.Game.Scenario.Topography.WorldDescription
 import Swarm.Game.Terrain
 import Swarm.Game.Universe
@@ -115,24 +112,6 @@ import System.Directory (doesFileExist)
 import System.FilePath ((<.>), (</>))
 import System.Random (randomRIO)
 
-type StructureCells = Structure.NamedGrid (Maybe Cell)
-
-data StaticStructureInfo = StaticStructureInfo
-  { _structureDefs :: [SymmetryAnnotatedGrid StructureCells]
-  , _staticPlacements :: M.Map SubworldName [Structure.LocatedStructure]
-  }
-  deriving (Show)
-
-makeLensesNoSigs ''StaticStructureInfo
-
--- | Structure templates that may be auto-recognized when constructed
--- by a robot
-structureDefs :: Lens' StaticStructureInfo [SymmetryAnnotatedGrid StructureCells]
-
--- | A record of the static placements of structures, so that they can be
--- added to the "recognized" list upon scenario initialization
-staticPlacements :: Lens' StaticStructureInfo (M.Map SubworldName [Structure.LocatedStructure])
-
 -- * Scenario records
 
 -- | Authorship information about scenario not used at play-time
@@ -211,7 +190,7 @@ data ScenarioLandscape = ScenarioLandscape
   , _scenarioKnown :: Set EntityName
   , _scenarioWorlds :: NonEmpty WorldDescription
   , _scenarioNavigation :: Navigation (M.Map SubworldName) Location
-  , _scenarioStructures :: StaticStructureInfo
+  , _scenarioStructures :: StaticStructureInfo Cell
   , _scenarioRobots :: [TRobot]
   }
   deriving (Show)
@@ -241,7 +220,7 @@ scenarioKnown :: Lens' ScenarioLandscape (Set EntityName)
 scenarioWorlds :: Lens' ScenarioLandscape (NonEmpty WorldDescription)
 
 -- | Information required for structure recognition
-scenarioStructures :: Lens' ScenarioLandscape StaticStructureInfo
+scenarioStructures :: Lens' ScenarioLandscape (StaticStructureInfo Cell)
 
 -- | Waypoints and inter-world portals
 scenarioNavigation :: Lens' ScenarioLandscape (Navigation (M.Map SubworldName) Location)
diff --git a/src/swarm-scenario/Swarm/Game/Scenario/Topography/Cell.hs b/src/swarm-scenario/Swarm/Game/Scenario/Topography/Cell.hs
index c82d52004..74557aa85 100644
--- a/src/swarm-scenario/Swarm/Game/Scenario/Topography/Cell.hs
+++ b/src/swarm-scenario/Swarm/Game/Scenario/Topography/Cell.hs
@@ -8,6 +8,7 @@ module Swarm.Game.Scenario.Topography.Cell (
   Cell,
   AugmentedCell,
   CellPaintDisplay,
+  cellToEntity,
 ) where
 
 import Control.Lens hiding (from, (.=), (<.>))
@@ -26,7 +27,7 @@ import Swarm.Game.Scenario.Topography.EntityFacade
 import Swarm.Game.Scenario.Topography.ProtoCell hiding (name)
 import Swarm.Game.Terrain
 import Swarm.Util (quote, showT)
-import Swarm.Util.Erasable (Erasable (..))
+import Swarm.Util.Erasable (Erasable (..), erasableToMaybe)
 import Swarm.Util.Yaml
 
 ------------------------------------------------------------
@@ -107,6 +108,9 @@ instance FromJSONE (TerrainEntityMaps, RobotMap) Cell where
 
     return $ Cell terr ent robs
 
+cellToEntity :: Maybe Cell -> Maybe Entity
+cellToEntity = ((erasableToMaybe . cellEntity) =<<)
+
 ------------------------------------------------------------
 -- World editor
 ------------------------------------------------------------
diff --git a/src/swarm-scenario/Swarm/Game/Scenario/Topography/WorldDescription.hs b/src/swarm-scenario/Swarm/Game/Scenario/Topography/WorldDescription.hs
index 99d837c93..729d087f0 100644
--- a/src/swarm-scenario/Swarm/Game/Scenario/Topography/WorldDescription.hs
+++ b/src/swarm-scenario/Swarm/Game/Scenario/Topography/WorldDescription.hs
@@ -29,7 +29,6 @@ import Swarm.Game.Scenario.Topography.ProtoCell (
   StructurePalette (StructurePalette),
  )
 import Swarm.Game.Scenario.Topography.Structure (
-  LocatedStructure,
   MergedStructure (MergedStructure),
   NamedStructure,
   parseStructure,
@@ -38,6 +37,7 @@ import Swarm.Game.Scenario.Topography.Structure.Assembly qualified as Assembly
 import Swarm.Game.Scenario.Topography.Structure.Overlay (
   PositionedGrid (..),
  )
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static (LocatedStructure)
 import Swarm.Game.Scenario.Topography.WorldPalette
 import Swarm.Game.Universe (SubworldName (DefaultRootSubworld))
 import Swarm.Game.World.Parse ()
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure.hs
index a917a6eaa..4d8b3dfaf 100644
--- a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure.hs
@@ -14,9 +14,7 @@ import Data.List (intercalate)
 import Data.List.NonEmpty qualified as NE
 import Data.Map qualified as M
 import Data.Maybe (catMaybes, fromMaybe)
-import Data.Set (Set)
 import Data.Set qualified as Set
-import Data.Text (Text)
 import Data.Text qualified as T
 import Data.Yaml as Y
 import Swarm.Game.Location
@@ -24,31 +22,13 @@ import Swarm.Game.Scenario.Topography.Grid
 import Swarm.Game.Scenario.Topography.Navigation.Waypoint
 import Swarm.Game.Scenario.Topography.Placement
 import Swarm.Game.Scenario.Topography.ProtoCell
+import Swarm.Game.Scenario.Topography.Structure.Named
 import Swarm.Game.Scenario.Topography.Structure.Overlay
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static
 import Swarm.Game.World.Coords
-import Swarm.Language.Syntax.Direction (AbsoluteDir)
 import Swarm.Util (failT, showT)
 import Swarm.Util.Yaml
 
-data NamedArea a = NamedArea
-  { name :: StructureName
-  , recognize :: Set AbsoluteDir
-  -- ^ whether this structure should be registered for automatic recognition
-  -- and which orientations shall be recognized.
-  -- The supplied direction indicates which cardinal direction the
-  -- original map's "North" has been re-oriented to.
-  -- E.g., 'DWest' represents a rotation of 90 degrees counter-clockwise.
-  , description :: Maybe Text
-  -- ^ will be UI-facing only if this is a recognizable structure
-  , structure :: a
-  }
-  deriving (Eq, Show, Functor)
-
-isRecognizable :: NamedArea a -> Bool
-isRecognizable = not . null . recognize
-
-type NamedGrid c = NamedArea (Grid c)
-
 type NamedStructure c = NamedArea (PStructure c)
 
 data PStructure c = Structure
@@ -64,18 +44,6 @@ data PStructure c = Structure
 data Placed c = Placed Placement (NamedStructure c)
   deriving (Show)
 
--- | For use in registering recognizable pre-placed structures
-data LocatedStructure = LocatedStructure
-  { placedName :: StructureName
-  , upDirection :: AbsoluteDir
-  , cornerLoc :: Location
-  }
-  deriving (Show)
-
-instance HasLocation LocatedStructure where
-  modifyLoc f (LocatedStructure x y originalLoc) =
-    LocatedStructure x y $ f originalLoc
-
 data MergedStructure c = MergedStructure (PositionedGrid c) [LocatedStructure] [Originated Waypoint]
 
 instance (FromJSONE e a) => FromJSONE e (NamedStructure (Maybe a)) where
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Assembly.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Assembly.hs
index 474b79ed5..06a6e12ac 100644
--- a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Assembly.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Assembly.hs
@@ -26,7 +26,9 @@ import Swarm.Game.Scenario.Topography.Grid
 import Swarm.Game.Scenario.Topography.Navigation.Waypoint
 import Swarm.Game.Scenario.Topography.Placement
 import Swarm.Game.Scenario.Topography.Structure
+import Swarm.Game.Scenario.Topography.Structure.Named
 import Swarm.Game.Scenario.Topography.Structure.Overlay
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static
 import Swarm.Language.Syntax.Direction (directionJsonModifier)
 import Swarm.Util (commaList, quote, showT)
 
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Named.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Named.hs
new file mode 100644
index 000000000..ad05a9874
--- /dev/null
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Named.hs
@@ -0,0 +1,28 @@
+-- |
+-- SPDX-License-Identifier: BSD-3-Clause
+module Swarm.Game.Scenario.Topography.Structure.Named where
+
+import Data.Set (Set)
+import Data.Text (Text)
+import Swarm.Game.Scenario.Topography.Grid (Grid)
+import Swarm.Game.Scenario.Topography.Placement (StructureName)
+import Swarm.Language.Syntax.Direction (AbsoluteDir)
+
+data NamedArea a = NamedArea
+  { name :: StructureName
+  , recognize :: Set AbsoluteDir
+  -- ^ whether this structure should be registered for automatic recognition
+  -- and which orientations shall be recognized.
+  -- The supplied direction indicates which cardinal direction the
+  -- original map's "North" has been re-oriented to.
+  -- E.g., 'DWest' represents a rotation of 90 degrees counter-clockwise.
+  , description :: Maybe Text
+  -- ^ will be UI-facing only if this is a recognizable structure
+  , structure :: a
+  }
+  deriving (Eq, Show, Functor)
+
+isRecognizable :: NamedArea a -> Bool
+isRecognizable = not . null . recognize
+
+type NamedGrid c = NamedArea (Grid c)
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition.hs
index c49906c95..457ac7fe8 100644
--- a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition.hs
@@ -24,7 +24,7 @@ makeLenses ''RecognitionState
 
 -- |
 -- The type parameters, `b`, and `a`, correspond
--- to 'StructureCells' and 'Entity', respectively.
+-- to 'Cell' and 'Entity', respectively.
 data StructureRecognizer b a = StructureRecognizer
   { _automatons :: RecognizerAutomatons b a
   -- ^ read-only
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Log.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Log.hs
index 26533ba8b..d8753d3c4 100644
--- a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Log.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Log.hs
@@ -12,13 +12,23 @@ import Servant.Docs qualified as SD
 import Swarm.Game.Location (Location)
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Type
 import Swarm.Game.Universe (Cosmic)
+import Swarm.Language.Syntax.Direction (AbsoluteDir)
 
 type StructureRowContent e = [Maybe e]
 type WorldRowContent e = [Maybe e]
 
+data OrientedStructure = OrientedStructure
+  { oName :: OriginalName
+  , oDir :: AbsoluteDir
+  }
+  deriving (Generic, ToJSON)
+
+distillLabel :: StructureWithGrid b a -> OrientedStructure
+distillLabel swg = OrientedStructure (getName $ originalDefinition swg) (rotatedTo swg)
+
 data MatchingRowFrom = MatchingRowFrom
   { rowIdx :: Int32
-  , structure :: OriginalName
+  , structure :: OrientedStructure
   }
   deriving (Generic, ToJSON)
 
@@ -26,7 +36,9 @@ newtype HaystackPosition = HaystackPosition Int
   deriving (Generic, ToJSON)
 
 data HaystackContext e = HaystackContext
-  { worldRow :: WorldRowContent e
+  { maskedWorldRow :: WorldRowContent e
+  -- ^ entities that do not constitute any of the eligible structures
+  -- are replaced with 'null' in this list.
   , haystackPosition :: HaystackPosition
   }
   deriving (Functor, Generic, ToJSON)
@@ -55,7 +67,10 @@ data SearchLog e
   = FoundParticipatingEntity (ParticipatingEntity e)
   | StructureRemoved OriginalName
   | FoundRowCandidates [FoundRowCandidate e]
-  | FoundCompleteStructureCandidates [OriginalName]
+  | FoundCompleteStructureCandidates [OrientedStructure]
+  | -- | There may be multiple candidate structures that could be
+    -- completed by the element that was just placed. This lists all of them.
+    VerticalSearchSpans [(InspectionOffsets, [OrientedStructure])]
   | IntactStaticPlacement [IntactPlacementLog]
   deriving (Functor, Generic)
 
diff --git a/src/swarm-scenario/Swarm/Game/Scenario/Topography/Structure/Recognition/Precompute.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Precompute.hs
similarity index 69%
rename from src/swarm-scenario/Swarm/Game/Scenario/Topography/Structure/Recognition/Precompute.hs
rename to src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Precompute.hs
index 18d2ef1b6..336643643 100644
--- a/src/swarm-scenario/Swarm/Game/Scenario/Topography/Structure/Recognition/Precompute.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Precompute.hs
@@ -41,75 +41,86 @@ module Swarm.Game.Scenario.Topography.Structure.Recognition.Precompute (
 ) where
 
 import Control.Arrow ((&&&))
+import Data.Hashable (Hashable)
 import Data.Map qualified as M
 import Data.Maybe (catMaybes, mapMaybe)
 import Data.Set qualified as Set
-import Swarm.Game.Entity (Entity)
-import Swarm.Game.Scenario (StaticStructureInfo (..), StructureCells)
-import Swarm.Game.Scenario.Topography.Cell (cellEntity)
 import Swarm.Game.Scenario.Topography.Grid (getRows)
 import Swarm.Game.Scenario.Topography.Placement (Orientation (..), applyOrientationTransform, getStructureName)
-import Swarm.Game.Scenario.Topography.Structure
-import Swarm.Game.Scenario.Topography.Structure qualified as Structure
-import Swarm.Game.Scenario.Topography.Structure.Recognition.Prep
-import Swarm.Game.Scenario.Topography.Structure.Recognition.Registry
+import Swarm.Game.Scenario.Topography.Structure.Named
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Prep (
+  mkEntityLookup,
+ )
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Registry (
+  populateStaticFoundStructures,
+ )
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Type
 import Swarm.Game.Universe (Cosmic (..))
 import Swarm.Language.Syntax.Direction (AbsoluteDir)
 import Swarm.Util (histogram)
-import Swarm.Util.Erasable (erasableToMaybe)
 
-getEntityGrid :: StructureCells -> [SymbolSequence Entity]
-getEntityGrid = getRows . fmap ((erasableToMaybe . cellEntity) =<<) . structure
+getEntityGrid :: (Maybe b -> Maybe a) -> NamedGrid (Maybe b) -> [[Maybe a]]
+getEntityGrid extractor = getRows . fmap extractor . structure
 
 -- | Create Aho-Corasick matchers that will recognize all of the
 -- provided structure definitions
 mkAutomatons ::
-  [SymmetryAnnotatedGrid StructureCells] ->
-  RecognizerAutomatons StructureCells Entity
-mkAutomatons xs =
+  (Ord a, Hashable a) =>
+  (Maybe b -> Maybe a) ->
+  [SymmetryAnnotatedGrid (Maybe b)] ->
+  RecognizerAutomatons (Maybe b) a
+mkAutomatons extractor xs =
   RecognizerAutomatons
     infos
     (mkEntityLookup rotatedGrids)
  where
-  rotatedGrids = concatMap (extractGrids . namedGrid) xs
+  rotatedGrids = concatMap (extractGrids extractor . namedGrid) xs
 
   process g = StructureInfo g entGrid countsMap
    where
-    entGrid = getEntityGrid $ namedGrid g
+    entGrid = getEntityGrid extractor $ namedGrid g
     countsMap = histogram $ concatMap catMaybes entGrid
 
   infos =
     M.fromList $
-      map (getStructureName . Structure.name . namedGrid &&& process) xs
+      map (getStructureName . name . namedGrid &&& process) xs
 
 extractOrientedGrid ::
-  StructureCells ->
+  (Maybe b -> Maybe a) ->
+  NamedGrid (Maybe b) ->
   AbsoluteDir ->
-  StructureWithGrid StructureCells Entity
-extractOrientedGrid x d =
-  StructureWithGrid wrapped d $ getEntityGrid g
+  StructureWithGrid (Maybe b) a
+extractOrientedGrid extractor x d =
+  StructureWithGrid wrapped d $ getEntityGrid extractor g
  where
-  wrapped = NamedOriginal (getStructureName $ Structure.name x) x
+  wrapped = NamedOriginal (getStructureName $ name x) x
   g = applyOrientationTransform (Orientation d False) <$> x
 
 -- | At this point, we have already ensured that orientations
 -- redundant by rotational symmetry have been excluded
 -- (i.e. at Scenario validation time).
-extractGrids :: StructureCells -> [StructureWithGrid StructureCells Entity]
-extractGrids x = map (extractOrientedGrid x) $ Set.toList $ recognize x
+extractGrids ::
+  (Maybe b -> Maybe a) ->
+  NamedGrid (Maybe b) ->
+  [StructureWithGrid (Maybe b) a]
+extractGrids extractor x =
+  map (extractOrientedGrid extractor x) $ Set.toList $ recognize x
 
 -- | The output list of 'FoundStructure' records is not yet
 -- vetted; the 'ensureStructureIntact' function will subsequently
 -- filter this list.
-lookupStaticPlacements :: StaticStructureInfo -> [FoundStructure StructureCells Entity]
-lookupStaticPlacements (StaticStructureInfo structDefs thePlacements) =
+lookupStaticPlacements ::
+  (Maybe b -> Maybe a) ->
+  StaticStructureInfo b ->
+  [FoundStructure (Maybe b) a]
+lookupStaticPlacements extractor (StaticStructureInfo structDefs thePlacements) =
   concatMap f $ M.toList thePlacements
  where
-  definitionMap = M.fromList $ map ((Structure.name &&& id) . namedGrid) structDefs
+  definitionMap = M.fromList $ map ((name &&& id) . namedGrid) structDefs
 
   f (subworldName, locatedList) = mapMaybe g locatedList
    where
     g (LocatedStructure theName d loc) = do
       sGrid <- M.lookup theName definitionMap
-      return $ FoundStructure (extractOrientedGrid sGrid d) $ Cosmic subworldName loc
+      return $ FoundStructure (extractOrientedGrid extractor sGrid d) $ Cosmic subworldName loc
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Registry.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Registry.hs
index 5109d51cc..1cdc14df6 100644
--- a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Registry.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Registry.hs
@@ -35,7 +35,7 @@ import Swarm.Util (binTuples, deleteKeys)
 -- | The authoritative source of which built structures currently exist.
 --
 -- The two type parameters, `b` and `a`, correspond
--- to 'StructureCells' and 'Entity', respectively.
+-- to 'Cell' and 'Entity', respectively.
 data FoundRegistry b a = FoundRegistry
   { _foundByName :: Map OriginalName (NEMap (Cosmic Location) (StructureWithGrid b a))
   , _foundByLocation :: Map (Cosmic Location) (FoundStructure b a)
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Static.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Static.hs
new file mode 100644
index 000000000..cde126dd9
--- /dev/null
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Static.hs
@@ -0,0 +1,57 @@
+{-# LANGUAGE TemplateHaskell #-}
+
+-- |
+-- SPDX-License-Identifier: BSD-3-Clause
+module Swarm.Game.Scenario.Topography.Structure.Recognition.Static where
+
+import Control.Lens (Lens')
+import Data.Map (Map)
+import Swarm.Game.Location
+import Swarm.Game.Scenario.Topography.Placement (StructureName)
+import Swarm.Game.Scenario.Topography.Structure.Named
+import Swarm.Game.Universe (SubworldName)
+import Swarm.Language.Syntax.Direction (AbsoluteDir)
+import Swarm.Util.Lens (makeLensesNoSigs)
+
+data RotationalSymmetry
+  = -- | Aka 1-fold symmetry
+    NoSymmetry
+  | -- | Equivalent under rotation by 180 degrees
+    TwoFold
+  | -- | Equivalent under rotation by 90 degrees
+    FourFold
+  deriving (Show, Eq)
+
+data SymmetryAnnotatedGrid a = SymmetryAnnotatedGrid
+  { namedGrid :: NamedGrid a
+  , symmetry :: RotationalSymmetry
+  }
+  deriving (Show)
+
+-- | For use in registering recognizable pre-placed structures
+data LocatedStructure = LocatedStructure
+  { placedName :: StructureName
+  , upDirection :: AbsoluteDir
+  , cornerLoc :: Location
+  }
+  deriving (Show)
+
+instance HasLocation LocatedStructure where
+  modifyLoc f (LocatedStructure x y originalLoc) =
+    LocatedStructure x y $ f originalLoc
+
+data StaticStructureInfo b = StaticStructureInfo
+  { _structureDefs :: [SymmetryAnnotatedGrid (Maybe b)]
+  , _staticPlacements :: Map SubworldName [LocatedStructure]
+  }
+  deriving (Show)
+
+makeLensesNoSigs ''StaticStructureInfo
+
+-- | Structure templates that may be auto-recognized when constructed
+-- by a robot
+structureDefs :: Lens' (StaticStructureInfo b) [SymmetryAnnotatedGrid (Maybe b)]
+
+-- | A record of the static placements of structures, so that they can be
+-- added to the "recognized" list upon scenario initialization
+staticPlacements :: Lens' (StaticStructureInfo b) (Map SubworldName [LocatedStructure])
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Symmetry.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Symmetry.hs
index 7ab5d67a5..6ca77ad69 100644
--- a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Symmetry.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Symmetry.hs
@@ -11,9 +11,8 @@ import Data.Map qualified as M
 import Data.Set qualified as Set
 import Data.Text qualified as T
 import Swarm.Game.Scenario.Topography.Placement (Orientation (..), applyOrientationTransform)
-import Swarm.Game.Scenario.Topography.Structure (NamedGrid)
-import Swarm.Game.Scenario.Topography.Structure qualified as Structure
-import Swarm.Game.Scenario.Topography.Structure.Recognition.Type (RotationalSymmetry (..), SymmetryAnnotatedGrid (..))
+import Swarm.Game.Scenario.Topography.Structure.Named (NamedGrid, recognize, structure)
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static (RotationalSymmetry (..), SymmetryAnnotatedGrid (..))
 import Swarm.Language.Syntax.Direction (AbsoluteDir (DSouth, DWest), getCoordinateOrientation)
 import Swarm.Util (commaList, failT, histogram, showT)
 
@@ -29,7 +28,7 @@ import Swarm.Util (commaList, failT, histogram, showT)
 --    2-fold symmetry.
 --    Warn if two opposite orientations were supplied.
 checkSymmetry ::
-  (MonadFail m, Eq a) => NamedGrid a -> m (SymmetryAnnotatedGrid (NamedGrid a))
+  (MonadFail m, Eq a) => NamedGrid a -> m (SymmetryAnnotatedGrid a)
 checkSymmetry ng = do
   case symmetryType of
     FourFold ->
@@ -66,5 +65,5 @@ checkSymmetry ng = do
   quarterTurnRows = applyOrientationTransform (Orientation DWest False) originalRows
   halfTurnRows = applyOrientationTransform (Orientation DSouth False) originalRows
 
-  suppliedOrientations = Structure.recognize ng
-  originalRows = Structure.structure ng
+  suppliedOrientations = recognize ng
+  originalRows = structure ng
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Tracking.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Tracking.hs
index 18f40b3a1..ee0076e98 100644
--- a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Tracking.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Tracking.hs
@@ -151,30 +151,41 @@ registerRowMatches ::
 registerRowMatches entLoader cLoc (AutomatonInfo participatingEnts horizontalOffsets sm) rState = do
   let registry = rState ^. foundStructures
 
-  entitiesRow <- getWorldRow entLoader registry participatingEnts cLoc horizontalOffsets 0
+  entitiesRow <-
+    getWorldRow
+      entLoader
+      registry
+      participatingEnts
+      cLoc
+      horizontalOffsets
+      0
+
   let candidates = findAll sm entitiesRow
+
       mkCandidateLogEntry c =
         FoundRowCandidate
           (HaystackContext entitiesRow (HaystackPosition $ pIndex c))
           (needleContent $ pVal c)
           rowMatchInfo
        where
+        rowMatchInfo :: [MatchingRowFrom]
         rowMatchInfo = NE.toList . NE.map (f . myRow) . singleRowItems $ pVal c
          where
           f x =
-            MatchingRowFrom (rowIndex x) $
-              getName . originalDefinition . wholeStructure $
-                x
+            MatchingRowFrom (rowIndex x) $ distillLabel . wholeStructure $ x
 
       logEntry = FoundRowCandidates $ map mkCandidateLogEntry candidates
+      rState2 = rState & recognitionLog %~ (logEntry :)
 
-  candidates2D <-
+  candidates2Dpairs <-
     forM candidates $
       checkVerticalMatch entLoader registry cLoc horizontalOffsets
 
+  let (verticalSpans, candidates2D) = unzip candidates2Dpairs
+      rState3 = rState2 & recognitionLog %~ (VerticalSearchSpans verticalSpans :)
+
   return $
-    registerStructureMatches (concat candidates2D) $
-      rState & recognitionLog %~ (logEntry :)
+    registerStructureMatches (concat candidates2D) rState3
 
 -- | Examines contiguous rows of entities, accounting
 -- for the offset of the initially found row.
@@ -186,10 +197,14 @@ checkVerticalMatch ::
   -- | Horizontal search offsets
   InspectionOffsets ->
   Position (StructureSearcher b a) ->
-  s [FoundStructure b a]
-checkVerticalMatch entLoader registry cLoc (InspectionOffsets (Min searchOffsetLeft) _) foundRow =
-  getMatches2D entLoader registry cLoc horizontalFoundOffsets $ automaton2D $ pVal foundRow
+  s ((InspectionOffsets, [OrientedStructure]), [FoundStructure b a])
+checkVerticalMatch entLoader registry cLoc (InspectionOffsets (Min searchOffsetLeft) _) foundRow = do
+  (x, y) <- getMatches2D entLoader registry cLoc horizontalFoundOffsets $ automaton2D searcherVal
+  return ((x, rowStructureNames), y)
  where
+  searcherVal = pVal foundRow
+  rowStructureNames = NE.toList . NE.map (distillLabel . wholeStructure . myRow) . singleRowItems $ searcherVal
+
   foundLeftOffset = searchOffsetLeft + fromIntegral (pIndex foundRow)
   foundRightInclusiveIndex = foundLeftOffset + fromIntegral (pLength foundRow) - 1
   horizontalFoundOffsets = InspectionOffsets (pure foundLeftOffset) (pure foundRightInclusiveIndex)
@@ -219,15 +234,15 @@ getMatches2D ::
   -- | Horizontal found offsets (inclusive indices)
   InspectionOffsets ->
   AutomatonInfo a (SymbolSequence a) (StructureWithGrid b a) ->
-  s [FoundStructure b a]
+  s (InspectionOffsets, [FoundStructure b a])
 getMatches2D
   entLoader
   registry
   cLoc
   horizontalFoundOffsets@(InspectionOffsets (Min offsetLeft) _)
-  (AutomatonInfo participatingEnts (InspectionOffsets (Min offsetTop) (Max offsetBottom)) sm) = do
+  (AutomatonInfo participatingEnts vRange@(InspectionOffsets (Min offsetTop) (Max offsetBottom)) sm) = do
     entityRows <- mapM getRow verticalOffsets
-    return $ getFoundStructures (offsetTop, offsetLeft) cLoc sm entityRows
+    return (vRange, getFoundStructures (offsetTop, offsetLeft) cLoc sm entityRows)
    where
     getRow = getWorldRow entLoader registry participatingEnts cLoc horizontalFoundOffsets
     verticalOffsets = [offsetTop .. offsetBottom]
@@ -238,9 +253,9 @@ getMatches2D
 -- The largest structure (by area) shall win.
 registerStructureMatches ::
   (Eq a, Eq b) =>
-  [FoundStructure a b] ->
-  RecognitionState a b ->
-  RecognitionState a b
+  [FoundStructure b a] ->
+  RecognitionState b a ->
+  RecognitionState b a
 registerStructureMatches unrankedCandidates oldState =
   oldState
     & (recognitionLog %~ (newMsg :))
@@ -249,5 +264,5 @@ registerStructureMatches unrankedCandidates oldState =
   -- Sorted by decreasing order of preference.
   rankedCandidates = sortOn Down unrankedCandidates
 
-  getStructName (FoundStructure swg _) = getName $ originalDefinition swg
-  newMsg = FoundCompleteStructureCandidates $ map getStructName rankedCandidates
+  getStructInfo (FoundStructure swg _) = distillLabel swg
+  newMsg = FoundCompleteStructureCandidates $ map getStructInfo rankedCandidates
diff --git a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Type.hs b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Type.hs
index 58bb25500..2d8f97934 100644
--- a/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Type.hs
+++ b/src/swarm-topography/Swarm/Game/Scenario/Topography/Structure/Recognition/Type.hs
@@ -35,6 +35,8 @@ import GHC.Generics (Generic)
 import Linear (V2 (..))
 import Swarm.Game.Location (Location)
 import Swarm.Game.Scenario.Topography.Area
+import Swarm.Game.Scenario.Topography.Structure.Named (NamedGrid)
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static
 import Swarm.Game.Universe (Cosmic, offsetBy)
 import Swarm.Language.Syntax.Direction (AbsoluteDir)
 import Text.AhoCorasick (StateMachine)
@@ -124,7 +126,7 @@ data SingleRowEntityOccurrences b a = SingleRowEntityOccurrences
 -- it's 'rowIndex' is @2@.
 --
 -- The two type parameters, `b` and `a`, correspond
--- to 'StructureCells' and 'Entity', respectively.
+-- to 'Cell' and 'Entity', respectively.
 data StructureRow b a = StructureRow
   { wholeStructure :: StructureWithGrid b a
   , rowIndex :: Int32
@@ -136,9 +138,9 @@ data StructureRow b a = StructureRow
 -- (i.e. the "payload" for recognition)
 -- for the purpose of both UI display and internal uniqueness,
 -- while remaining agnostic to its internals.
-data NamedOriginal a = NamedOriginal
+data NamedOriginal b = NamedOriginal
   { getName :: OriginalName
-  , orig :: a
+  , orig :: NamedGrid b
   }
   deriving (Show, Eq)
 
@@ -146,7 +148,7 @@ data NamedOriginal a = NamedOriginal
 -- with its grid of cells having been extracted for convenience.
 --
 -- The two type parameters, `b` and `a`, correspond
--- to 'StructureCells' and 'Entity', respectively.
+-- to 'Cell' and 'Entity', respectively.
 data StructureWithGrid b a = StructureWithGrid
   { originalDefinition :: NamedOriginal b
   , rotatedTo :: AbsoluteDir
@@ -154,21 +156,6 @@ data StructureWithGrid b a = StructureWithGrid
   }
   deriving (Eq)
 
-data RotationalSymmetry
-  = -- | Aka 1-fold symmetry
-    NoSymmetry
-  | -- | Equivalent under rotation by 180 degrees
-    TwoFold
-  | -- | Equivalent under rotation by 90 degrees
-    FourFold
-  deriving (Show, Eq)
-
-data SymmetryAnnotatedGrid a = SymmetryAnnotatedGrid
-  { namedGrid :: a
-  , symmetry :: RotationalSymmetry
-  }
-  deriving (Show)
-
 -- | Structure definitions with precomputed metadata for consumption by the UI
 data StructureInfo b a = StructureInfo
   { annotatedGrid :: SymmetryAnnotatedGrid b
@@ -231,7 +218,7 @@ makeLenses ''RecognizerAutomatons
 -- These are the elements that are stored in the 'FoundRegistry'.
 --
 -- The two type parameters, `b` and `a`, correspond
--- to 'StructureCells' and 'Entity', respectively.
+-- to 'Cell' and 'Entity', respectively.
 data FoundStructure b a = FoundStructure
   { structureWithGrid :: StructureWithGrid b a
   , upperLeftCorner :: Cosmic Location
diff --git a/src/swarm-tui/Swarm/TUI/Model/Structure.hs b/src/swarm-tui/Swarm/TUI/Model/Structure.hs
index d4f1ce303..73a8c23d5 100644
--- a/src/swarm-tui/Swarm/TUI/Model/Structure.hs
+++ b/src/swarm-tui/Swarm/TUI/Model/Structure.hs
@@ -12,12 +12,12 @@ import Brick.Widgets.List qualified as BL
 import Control.Lens (makeLenses)
 import Data.List.Extra (enumerate)
 import Swarm.Game.Entity (Entity)
-import Swarm.Game.Scenario (StructureCells)
+import Swarm.Game.Scenario.Topography.Cell (Cell)
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Type
 import Swarm.TUI.Model.Name
 
 data StructureDisplay = StructureDisplay
-  { _structurePanelListWidget :: BL.List Name (StructureInfo StructureCells Entity)
+  { _structurePanelListWidget :: BL.List Name (StructureInfo (Maybe Cell) Entity)
   -- ^ required for maintaining the selection/navigation
   -- state among list items
   , _structurePanelFocus :: FocusRing Name
diff --git a/src/swarm-tui/Swarm/TUI/View/Structure.hs b/src/swarm-tui/Swarm/TUI/View/Structure.hs
index 1a43a9139..24d458114 100644
--- a/src/swarm-tui/Swarm/TUI/View/Structure.hs
+++ b/src/swarm-tui/Swarm/TUI/View/Structure.hs
@@ -20,13 +20,14 @@ import Data.Set qualified as Set
 import Data.Text qualified as T
 import Data.Vector qualified as V
 import Swarm.Game.Entity (Entity, entityDisplay)
-import Swarm.Game.Scenario (StructureCells)
 import Swarm.Game.Scenario.Topography.Area
+import Swarm.Game.Scenario.Topography.Cell (Cell, cellToEntity)
 import Swarm.Game.Scenario.Topography.Placement (getStructureName)
-import Swarm.Game.Scenario.Topography.Structure qualified as Structure
+import Swarm.Game.Scenario.Topography.Structure.Named qualified as Structure
 import Swarm.Game.Scenario.Topography.Structure.Recognition (foundStructures, recognitionState)
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Precompute (getEntityGrid)
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Registry (foundByName)
+import Swarm.Game.Scenario.Topography.Structure.Recognition.Static
 import Swarm.Game.Scenario.Topography.Structure.Recognition.Type
 import Swarm.Game.State
 import Swarm.Game.State.Substate (structureRecognition)
@@ -40,7 +41,7 @@ import Swarm.Util (commaList)
 
 -- | Render a two-pane widget with structure selection on the left
 -- and single-structure details on the right.
-structureWidget :: GameState -> StructureInfo StructureCells Entity -> Widget n
+structureWidget :: GameState -> StructureInfo (Maybe Cell) Entity -> Widget n
 structureWidget gs s =
   vBox
     [ hBox
@@ -118,10 +119,10 @@ structureWidget gs s =
       ]
 
   theName = getStructureName $ Structure.name d
-  cells = getEntityGrid d
+  cells = getEntityGrid cellToEntity d
   renderOneCell = maybe (txt " ") (renderDisplay . view entityDisplay)
 
-makeListWidget :: [StructureInfo StructureCells Entity] -> BL.List Name (StructureInfo StructureCells Entity)
+makeListWidget :: [StructureInfo (Maybe Cell) Entity] -> BL.List Name (StructureInfo (Maybe Cell) Entity)
 makeListWidget structureDefinitions =
   BL.listMoveTo 0 $ BL.list (StructureWidgets StructuresList) (V.fromList structureDefinitions) 1
 
@@ -163,7 +164,7 @@ renderStructuresDisplay gs structureDisplay =
 
 drawSidebarListItem ::
   Bool ->
-  StructureInfo StructureCells Entity ->
+  StructureInfo (Maybe Cell) Entity ->
   Widget Name
 drawSidebarListItem _isSelected (StructureInfo annotated _ _) =
   txt . getStructureName . Structure.name $ namedGrid annotated
diff --git a/swarm.cabal b/swarm.cabal
index 7fa4bc3fb..551a0fc94 100644
--- a/swarm.cabal
+++ b/swarm.cabal
@@ -221,11 +221,14 @@ library swarm-topography
     Swarm.Game.Scenario.Topography.Rasterize
     Swarm.Game.Scenario.Topography.Structure
     Swarm.Game.Scenario.Topography.Structure.Assembly
+    Swarm.Game.Scenario.Topography.Structure.Named
     Swarm.Game.Scenario.Topography.Structure.Overlay
     Swarm.Game.Scenario.Topography.Structure.Recognition
     Swarm.Game.Scenario.Topography.Structure.Recognition.Log
+    Swarm.Game.Scenario.Topography.Structure.Recognition.Precompute
     Swarm.Game.Scenario.Topography.Structure.Recognition.Prep
     Swarm.Game.Scenario.Topography.Structure.Recognition.Registry
+    Swarm.Game.Scenario.Topography.Structure.Recognition.Static
     Swarm.Game.Scenario.Topography.Structure.Recognition.Symmetry
     Swarm.Game.Scenario.Topography.Structure.Recognition.Tracking
     Swarm.Game.Scenario.Topography.Structure.Recognition.Type
@@ -297,7 +300,6 @@ library swarm-scenario
     Swarm.Game.Scenario.Topography.Center
     Swarm.Game.Scenario.Topography.EntityFacade
     Swarm.Game.Scenario.Topography.Navigation.Portal
-    Swarm.Game.Scenario.Topography.Structure.Recognition.Precompute
     Swarm.Game.Scenario.Topography.WorldDescription
     Swarm.Game.Scenario.Topography.WorldPalette
     Swarm.Game.State.Config
diff --git a/weeder.toml b/weeder.toml
index 695e0c1c1..b93e5806c 100644
--- a/weeder.toml
+++ b/weeder.toml
@@ -51,8 +51,8 @@ roots = [
     "^Swarm.Language.Typed.requires$",
     "^Swarm.Language.Typed.value$",
     "^Swarm.Language.Value.emptyEnv$",
-    "^Swarm.Game.Scenario.staticPlacements$",
-    "^Swarm.Game.Scenario.structureDefs$",
+    "^Swarm.Game.Scenario.Topography.Structure.Recognition.Static.staticPlacements$",
+    "^Swarm.Game.Scenario.Topography.Structure.Recognition.Static.structureDefs$",
     "^Swarm.Game.Scenario.Scoring.Best.scenarioBestByAstSize$",
     "^Swarm.Game.Scenario.Scoring.Best.scenarioBestByCharCount$",
     "^Swarm.Game.Scenario.Scoring.Best.scenarioBestByTicks$",