diff --git a/src/table/settings.ini b/src/table/settings.ini
--- a/src/table/settings.ini
+++ b/src/table/settings.ini
@@ -2178,8 +2178,8 @@ type     = SLE_UINT8
 from     = 30
 guiflags = SGF_MULTISTRING | SGF_NEWGAME_ONLY
 def      = 1
-min      = 0
-max      = 3
+min      = TGEN_SMOOTHNESS_BEGIN
+max      = TGEN_SMOOTHNESS_END - 1
 str      = STR_CONFIG_SETTING_ROUGHNESS_OF_TERRAIN
 strhelp  = STR_CONFIG_SETTING_ROUGHNESS_OF_TERRAIN_HELPTEXT
 strval   = STR_CONFIG_SETTING_ROUGHNESS_OF_TERRAIN_VERY_SMOOTH