diff --git a/lib/rmg/CMapGenerator.cpp b/lib/rmg/CMapGenerator.cpp
index fcfe4b697..a18d0a056 100644
--- a/lib/rmg/CMapGenerator.cpp
+++ b/lib/rmg/CMapGenerator.cpp
@@ -518,6 +518,8 @@ void CMapGenerator::createConnections()
 			int3 tile = posA;
 			int3 otherTile = tile;
 
+			auto sgt = VLC->objtypeh->getHandlerFor(Obj::SUBTERRANEAN_GATE, 0)->getTemplates().front();
+
 			bool stop = false;
 			while (!stop)
 			{
@@ -551,11 +553,15 @@ void CMapGenerator::createConnections()
 								withinZone = false;
 						});
 
-						if (withinZone)
+						//make sure both gates has some free tiles below them
+						if (zoneA->getAccessibleOffset(this, sgt, tile).valid() && zoneB->getAccessibleOffset(this, sgt, otherTile).valid())
 						{
-							zoneA->placeSubterraneanGate(this, tile, connection.getGuardStrength());
-							zoneB->placeSubterraneanGate(this, otherTile, connection.getGuardStrength());
-							stop = true; //we are done, go to next connection
+							if (withinZone)
+							{
+								zoneA->placeSubterraneanGate(this, tile, connection.getGuardStrength());
+								zoneB->placeSubterraneanGate(this, otherTile, connection.getGuardStrength());
+								stop = true; //we are done, go to next connection
+							}
 						}
 					}
 				}
diff --git a/lib/rmg/CRmgTemplateZone.h b/lib/rmg/CRmgTemplateZone.h
index d71e2acc9..6fe06486e 100644
--- a/lib/rmg/CRmgTemplateZone.h
+++ b/lib/rmg/CRmgTemplateZone.h
@@ -147,6 +147,8 @@ public:
 	void setCenter(const float3 &f);
 	int3 getPos() const;
 	void setPos(const int3 &pos);
+	bool isAccessibleFromAnywhere(CMapGenerator* gen, ObjectTemplate &appearance, int3 &tile) const;
+	int3 getAccessibleOffset(CMapGenerator* gen, ObjectTemplate &appearance, int3 &tile) const;
 
 	void addTile (const int3 &pos);
 	void initFreeTiles (CMapGenerator* gen);
@@ -239,8 +241,6 @@ private:
 
 	bool pointIsIn(int x, int y);
 	void addAllPossibleObjects (CMapGenerator* gen); //add objects, including zone-specific, to possibleObjects
-	bool isAccessibleFromAnywhere (CMapGenerator* gen, ObjectTemplate &appearance, int3 &tile) const;
-	int3 getAccessibleOffset(CMapGenerator* gen, ObjectTemplate &appearance, int3 &tile) const;
 	bool findPlaceForObject(CMapGenerator* gen, CGObjectInstance* obj, si32 min_dist, int3 &pos);
 	bool findPlaceForTreasurePile(CMapGenerator* gen, float min_dist, int3 &pos, int value);
 	bool canObstacleBePlacedHere(CMapGenerator* gen, ObjectTemplate &temp, int3 &pos);