diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs b/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
index 834228e992..d993e6a070 100755
--- a/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSParam.cs
@@ -538,7 +538,7 @@ public static class BSParam
             (s,o) => { s.PE.SetContactProcessingThreshold(o.PhysBody, ContactProcessingThreshold); } ),
 
 	    new ParameterDefn<float>("TerrainImplementation", "Type of shape to use for terrain (0=heightmap, 1=mesh)",
-            (float)BSTerrainPhys.TerrainImplementation.Mesh ),
+            (float)BSTerrainPhys.TerrainImplementation.Heightmap ),
         new ParameterDefn<int>("TerrainMeshMagnification", "Number of times the 256x256 heightmap is multiplied to create the terrain mesh" ,
             2 ),
         new ParameterDefn<float>("TerrainFriction", "Factor to reduce movement against terrain surface" ,
diff --git a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
index fe014fcafe..2d2e55f34c 100644
--- a/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
+++ b/OpenSim/Region/Physics/BulletSPlugin/BSScene.cs
@@ -235,6 +235,14 @@ public sealed class BSScene : PhysicsScene, IPhysicsParameters
         // Set default values for physics parameters plus any overrides from the ini file
         GetInitialParameterValues(config);
 
+        // Force some parameters to values depending on other configurations
+        // Only use heightmap terrain implementation if terrain larger than legacy size
+        if ((uint)regionExtent.X > Constants.RegionSize || (uint)regionExtent.Y > Constants.RegionSize)
+        {
+            m_log.WarnFormat("{0} Forcing terrain implementation to heightmap for large region", LogHeader);
+            BSParam.TerrainImplementation = (float)BSTerrainPhys.TerrainImplementation.Heightmap;
+        }
+
         // Get the connection to the physics engine (could be native or one of many DLLs)
         PE = SelectUnderlyingBulletEngine(BulletEngineName);
 
diff --git a/bin/OpenSimDefaults.ini b/bin/OpenSimDefaults.ini
index df94239801..026f285707 100644
--- a/bin/OpenSimDefaults.ini
+++ b/bin/OpenSimDefaults.ini
@@ -1001,10 +1001,10 @@
 
     ; Terrain implementation can use either Bullet's heightField or BulletSim can build
     ;   a mesh. 0=heightField, 1=mesh
-    TerrainImplementation = 1
+    TerrainImplementation = 0
     ; For mesh terrain, the detail of the created mesh. '1' gives 256x256 (heightfield
     ;   resolution). '2' gives 512x512. Etc. Cannot be larger than '4'. Higher
-    ;   magnification uses lots of memory.
+    ;   magnifications use lots of memory.
     TerrainMeshMagnification = 2
 
     ; Avatar physics height adjustments.