--- a/openttd.c
+++ b/openttd.c
@@ -1210,22 +1210,22 @@
 	 *  all about ;) */
 	if (CheckSavegameVersionOldStyle(6, 1)) {
 		BEGIN_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0) {
-			if (IsTileType(tile, MP_HOUSE)) {
-				_m[tile].m4 = _m[tile].m2;
-				//XXX magic
-				SetTileType(tile, MP_VOID);
-				_m[tile].m2 = ClosestTownFromTile(tile,(uint)-1)->index;
-				SetTileType(tile, MP_HOUSE);
-			} else if (IsTileType(tile, MP_STREET)) {
-				//XXX magic
-				_m[tile].m4 |= (_m[tile].m2 << 4);
-				if (IsTileOwner(tile, OWNER_TOWN)) {
-					SetTileType(tile, MP_VOID);
-					_m[tile].m2 = ClosestTownFromTile(tile,(uint)-1)->index;
-					SetTileType(tile, MP_STREET);
-				} else {
-					SetTownIndex(tile, 0);
-				}
+			switch (GetTileType(tile)) {
+				case MP_HOUSE:
+					_m[tile].m4 = _m[tile].m2;
+					SetTownIndex(tile, CalcClosestTownFromTile(tile, (uint)-1)->index);
+					break;
+
+				case MP_STREET:
+					_m[tile].m4 |= (_m[tile].m2 << 4);
+					if (IsTileOwner(tile, OWNER_TOWN)) {
+						SetTownIndex(tile, CalcClosestTownFromTile(tile, (uint)-1)->index);
+					} else {
+						SetTownIndex(tile, 0);
+					}
+					break;
+
+				default: break;
 			}
 		} END_TILE_LOOP(tile, MapSizeX(), MapSizeY(), 0);
 	}

--- a/town_cmd.c
+++ b/town_cmd.c
@@ -1739,18 +1739,12 @@
 }
 
 
-Town *ClosestTownFromTile(TileIndex tile, uint threshold)
+Town* CalcClosestTownFromTile(TileIndex tile, uint threshold)
 {
 	Town *t;
 	uint dist, best = threshold;
 	Town *best_town = NULL;
 
-	if (IsTileType(tile, MP_HOUSE) || (
-				IsTileType(tile, MP_STREET) &&
-				(IsLevelCrossing(tile) ? GetCrossingRoadOwner(tile) : GetTileOwner(tile)) == OWNER_TOWN
-			))
-		return GetTownByTile(tile);
-
 	FOR_ALL_TOWNS(t) {
 		if (t->xy != 0) {
 			dist = DistanceManhattan(tile, t->xy);
@@ -1764,6 +1758,20 @@
 	return best_town;
 }
 
+
+Town *ClosestTownFromTile(TileIndex tile, uint threshold)
+{
+	if (IsTileType(tile, MP_HOUSE) || (
+				IsTileType(tile, MP_STREET) &&
+				(IsLevelCrossing(tile) ? GetCrossingRoadOwner(tile) : GetTileOwner(tile)) == OWNER_TOWN
+			)) {
+		return GetTownByTile(tile);
+	} else {
+		return CalcClosestTownFromTile(tile, threshold);
+	}
+}
+
+
 void ChangeTownRating(Town *t, int add, int max)
 {
 	int rating;

--- a/town_map.h
+++ b/town_map.h
@@ -20,14 +20,13 @@
 }
 
 /**
- * Set the town index for a street tile.
+ * Set the town index for a road or house tile.
  * @param tile the tile
  * @param index the index of the town
- * @pre IsTileType(tile, MP_STREET)
  */
 static inline void SetTownIndex(TileIndex t, TownID index)
 {
-	assert(IsTileType(t, MP_STREET));
+	assert(IsTileType(t, MP_STREET) || IsTileType(t, MP_HOUSE));
 	_m[t].m2 = index;
 }
 
@@ -81,6 +80,10 @@
 	return GetTown(GetTownIndex(t));
 }
 
+
+Town* CalcClosestTownFromTile(TileIndex tile, uint threshold);
+
+
 static inline void MakeHouseTile(TileIndex t, TownID tid, byte counter, byte stage, byte type)
 {
 	assert(IsTileType(t, MP_CLEAR));