diff --git a/docs/source/index.md b/docs/source/index.md
index e14962087..bfe286109 100644
--- a/docs/source/index.md
+++ b/docs/source/index.md
@@ -35,6 +35,7 @@ how-to/tiled-authn-database
 ```{toctree}
 :caption: Explanations
 
+explanations/architecture
 explanations/standards
 explanations/structures
 explanations/metadata