diff --git a/Maps.md b/Maps.md
index d59d707..1eac3bb 100644
--- a/Maps.md
+++ b/Maps.md
@@ -39,6 +39,14 @@ Index | Description
 
 ## Surface Elements
 
+| Byte | Offset Name | Notes
+|-----|-------------|------
+| 0 | Type | 0bE?YY_YY?T where E is vertical edge style (extra bit), T is terrain style (extra bit)
+| 4 | Slope | 0bEEES_SSSS where E is the vertical edge style, S is slope
+| 5 | Terrain | 0bTTTW_WWWW where T is terrain style, W is water height.
+| 6 | Grass Length | 0 to 6 (0 = Mowed, 1 = Clear, 4 = Clumps)
+| 7 | Ownership | 0bOOOO_FFFF where O is ownership flags and F are park fence direction flags.
+
 ## Path Elements
 
 ## Track Elements