diff --git a/src/BasicPathFinding.cs b/src/BasicPathFinding.cs
index 8d7e752..af06229 100644
--- a/src/BasicPathFinding.cs
+++ b/src/BasicPathFinding.cs
@@ -142,7 +142,7 @@ namespace OpenSim.Modules.PathFinding
             {
                 for (int Y = 0; Y < m_scene.RegionInfo.RegionSizeY; Y++)
                 {
-                    float baseheight = (float)m_scene.Heightmap[X, Y];
+                    float baseheight = (float)m_scene.Heightmap[Y, X];
 
                     if (baseheight <= m_scene.RegionInfo.RegionSettings.WaterHeight)
                         _map.SetPixel(X, Y, Color.Blue);