diff --git a/Data-model.md b/Data-model.md
index c631a26..e4d2700 100644
--- a/Data-model.md
+++ b/Data-model.md
@@ -64,6 +64,7 @@ Features represent separate locked areas like islands, lakes and oceans.
 * * `cells`: `number` - number of cells in feature
 * * `firstCell`: `number` - index of the first (top left) cell in feature 
 * * `vertices`: `number[]` - indexes of vertices around the feature (perimetric vertices)
+** `name`: `string` - name, available for `lake` type only
 
 ## Specific cells data
 World data is mainly stored in typed arrays within `cells` object in both `grid` and `pack`.