diff --git a/src/world/map.c b/src/world/map.c
index 0194509789..0926e655c0 100644
--- a/src/world/map.c
+++ b/src/world/map.c
@@ -2051,12 +2051,12 @@ void game_command_lower_land(int* eax, int* ebx, int* ecx, int* edx, int* esi, i
 	);
 }
 
-static int map_get_corner_height(rct_map_element *mapElement, int slopeMask)
+static int map_get_corner_height(rct_map_element *mapElement, int direction)
 {
 	int z = mapElement->base_height;
 	int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-	switch (slopeMask) {
-	case 1:
+	switch (direction) {
+	case 0:
 		if (slope & 1) {
 			z += 2;
 			if (slope == 27) {
@@ -2064,7 +2064,7 @@ static int map_get_corner_height(rct_map_element *mapElement, int slopeMask)
 			}
 		}
 		break;
-	case 2:
+	case 1:
 		if (slope & 2) {
 			z += 2;
 			if (slope == 23) {
@@ -2072,7 +2072,7 @@ static int map_get_corner_height(rct_map_element *mapElement, int slopeMask)
 			}
 		}
 		break;
-	case 4:
+	case 2:
 		if (slope & 4) {
 			z += 2;
 			if (slope == 30) {
@@ -2080,7 +2080,7 @@ static int map_get_corner_height(rct_map_element *mapElement, int slopeMask)
 			}
 		}
 		break;
-	case 8:
+	case 3:
 		if (slope & 8) {
 			z += 2;
 			if (slope == 29) {
@@ -2094,9 +2094,12 @@ static int map_get_corner_height(rct_map_element *mapElement, int slopeMask)
 
 /**
  *
- *  rct2: 0x0068C3B2
+ *  rct2: 0x0068C3B2 slope 1, style 0
+ *  rct2: 0x0068C47A slope 2, style 1
+ *  rct2: 0x0068C222 slope 4, style 2
+ *  rct2: 0x0068C2EA slope 8, style 3
  */
-static money32 sub_68C3B2(uint8 flags, int x, int y, uint8 targetBaseZ, uint8 minBaseZ)
+static money32 smooth_land_tile(int direction, uint8 flags, int x, int y, uint8 targetBaseZ, uint8 minBaseZ)
 {
 	// Check if inside map bounds
 	if (x < 0 || y < 0 || x >= (256 * 32) || y >= (256 * 32)) {
@@ -2105,7 +2108,7 @@ static money32 sub_68C3B2(uint8 flags, int x, int y, uint8 targetBaseZ, uint8 mi
 
 	// Get height of tile
 	rct_map_element *mapElement = map_get_surface_element_at(x >> 5, y >> 5);
-	uint8 baseZ = map_get_corner_height(mapElement, 1);
+	uint8 baseZ = map_get_corner_height(mapElement, direction);
 
 	// Check if tile is same height as target tile
 	if (baseZ == targetBaseZ) {
@@ -2121,7 +2124,7 @@ static money32 sub_68C3B2(uint8 flags, int x, int y, uint8 targetBaseZ, uint8 mi
 		}
 		targetBaseZ = mapElement->base_height;
 		int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-		style = map_element_lower_styles[0][slope];
+		style = map_element_lower_styles[direction][slope];
 		if (style & 0x20) {
 			targetBaseZ -= 2;
 			style &= ~0x20;
@@ -2133,7 +2136,7 @@ static money32 sub_68C3B2(uint8 flags, int x, int y, uint8 targetBaseZ, uint8 mi
 		}
 		targetBaseZ = mapElement->base_height;
 		int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-		style = map_element_raise_styles[0][slope];
+		style = map_element_raise_styles[direction][slope];
 		if ((style & 0x20) != 0) {
 			targetBaseZ += 2;
 			style &= ~0x20;
@@ -2143,180 +2146,12 @@ static money32 sub_68C3B2(uint8 flags, int x, int y, uint8 targetBaseZ, uint8 mi
 	return game_do_command(x, flags, y, targetBaseZ | (style << 8), GAME_COMMAND_SET_LAND_HEIGHT, 0, 0);
 }
 
-/**
- *
- *  rct2: 0x0068C47A
- */
-static money32 sub_68C47A(uint8 flags, int x, int y, uint8 targetBaseZ, uint8 minBaseZ)
+money32 smooth_land(int flags, int centreX, int centreY, int mapLeft, int mapTop, int mapRight, int mapBottom, int command)
 {
-	// Check if inside map bounds
-	if (x < 0 || y < 0 || x >= (256 * 32) || y >= (256 * 32)) {
-		return MONEY32_UNDEFINED;
-	}
-
-	// Get height of tile
-	rct_map_element *mapElement = map_get_surface_element_at(x >> 5, y >> 5);
-	uint8 baseZ = map_get_corner_height(mapElement, 2);
-
-	// Check if tile is same height as target tile
-	if (baseZ == targetBaseZ) {
-		// No need to raise or lower
-		return MONEY32_UNDEFINED;
-	}
-
-	uint8 style;
-	if (targetBaseZ <= baseZ) {
-		baseZ = baseZ - targetBaseZ;
-		if (baseZ <= minBaseZ) {
-			return MONEY32_UNDEFINED;
-		}
-		targetBaseZ = mapElement->base_height;
-		int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-		style = map_element_lower_styles[1][slope];
-		if (style & 0x20) {
-			targetBaseZ -= 2;
-			style &= ~0x20;
-		}
-	} else {
-		baseZ = targetBaseZ - baseZ;
-		if (baseZ <= minBaseZ) {
-			return MONEY32_UNDEFINED;
-		}
-		targetBaseZ = mapElement->base_height;
-		int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-		style = map_element_raise_styles[1][slope];
-		if ((style & 0x20) != 0) {
-			targetBaseZ += 2;
-			style &= ~0x20;
-		}
-	}
-
-	return game_do_command(x, flags, y, targetBaseZ | (style << 8), GAME_COMMAND_SET_LAND_HEIGHT, 0, 0);
-}
-
-/**
- *
- *  rct2: 0x0068C222
- */
-static money32 sub_68C222(uint8 flags, int x, int y, uint8 targetBaseZ, uint8 minBaseZ)
-{
-	// Check if inside map bounds
-	if (x < 0 || y < 0 || x >= (256 * 32) || y >= (256 * 32)) {
-		return MONEY32_UNDEFINED;
-	}
-
-	// Get height of tile
-	rct_map_element *mapElement = map_get_surface_element_at(x >> 5, y >> 5);
-	uint8 baseZ = map_get_corner_height(mapElement, 4);
-
-	// Check if tile is same height as target tile
-	if (baseZ == targetBaseZ) {
-		// No need to raise or lower
-		return MONEY32_UNDEFINED;
-	}
-
-	uint8 style;
-	if (targetBaseZ <= baseZ) {
-		baseZ = baseZ - targetBaseZ;
-		if (baseZ <= minBaseZ) {
-			return MONEY32_UNDEFINED;
-		}
-		targetBaseZ = mapElement->base_height;
-		int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-		style = map_element_lower_styles[2][slope];
-		if (style & 0x20) {
-			targetBaseZ -= 2;
-			style &= ~0x20;
-		}
-	} else {
-		baseZ = targetBaseZ - baseZ;
-		if (baseZ <= minBaseZ) {
-			return MONEY32_UNDEFINED;
-		}
-		targetBaseZ = mapElement->base_height;
-		int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-		style = map_element_raise_styles[2][slope];
-		if ((style & 0x20) != 0) {
-			targetBaseZ += 2;
-			style &= ~0x20;
-		}
-	}
-
-	return game_do_command(x, flags, y, targetBaseZ | (style << 8), GAME_COMMAND_SET_LAND_HEIGHT, 0, 0);
-}
-
-/**
- *
- *  rct2: 0x0068C2EA
- */
-static money32 sub_68C2EA(uint8 flags, int x, int y, uint8 targetBaseZ, uint8 minBaseZ)
-{
-	// Check if inside map bounds
-	if (x < 0 || y < 0 || x >= (256 * 32) || y >= (256 * 32)) {
-		return MONEY32_UNDEFINED;
-	}
-
-	// Get height of tile
-	rct_map_element *mapElement = map_get_surface_element_at(x >> 5, y >> 5);
-	uint8 baseZ = map_get_corner_height(mapElement, 8);
-
-	// Check if tile is same height as target tile
-	if (baseZ == targetBaseZ) {
-		// No need to raise or lower
-		return MONEY32_UNDEFINED;
-	}
-
-	uint8 style;
-	if (targetBaseZ <= baseZ) {
-		baseZ = baseZ - targetBaseZ;
-		if (baseZ <= minBaseZ) {
-			return MONEY32_UNDEFINED;
-		}
-		targetBaseZ = mapElement->base_height;
-		int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-		style = map_element_lower_styles[3][slope];
-		if (style & 0x20) {
-			targetBaseZ -= 2;
-			style &= ~0x20;
-		}
-	} else {
-		baseZ = targetBaseZ - baseZ;
-		if (baseZ <= minBaseZ) {
-			return MONEY32_UNDEFINED;
-		}
-		targetBaseZ = mapElement->base_height;
-		int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-		style = map_element_raise_styles[3][slope];
-		if ((style & 0x20) != 0) {
-			targetBaseZ += 2;
-			style &= ~0x20;
-		}
-	}
-
-	return game_do_command(x, flags, y, targetBaseZ | (style << 8), GAME_COMMAND_SET_LAND_HEIGHT, 0, 0);
-}
-
-/**
- *
- *  rct2: 0x0068BC01
- */
-void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi, int* edi, int* ebp)
-{
-	// RCT2_CALLFUNC_X(0x0068BC01, eax, ebx, ecx, edx, esi, edi, ebp); return;
-
-	int flags = *ebx & 0xFF;
-	int centreX = *eax & 0xFFFF;
-	int centreY = *ecx & 0xFFFF;
+	int commandType;
 	int centreZ = map_element_height(centreX, centreY);
-	int mapLeftRight = *edx;
-	int mapTopBottom = *ebp;
-	int mapLeft = mapLeftRight & 0xFFFF;
-	int mapTop = mapTopBottom & 0xFFFF;
-	int mapRight = mapLeftRight >> 16;
-	int mapBottom = mapTopBottom >> 16;
-
-	int subCommand = *edi;
-	int subGameCommandType = *edi == 1 ? GAME_COMMAND_RAISE_LAND : GAME_COMMAND_LOWER_LAND;
+	int mapLeftRight = mapLeft | (mapRight << 16);
+	int mapTopBottom = mapTop | (mapBottom << 16);
 
 	// Play sound (only once)
 	if ((flags & GAME_COMMAND_FLAG_APPLY) && RCT2_GLOBAL(0x009A8C28, uint8) == 1) {
@@ -2327,7 +2162,8 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 
 	// First raise / lower the centre tile
 	money32 result;
-	result = game_do_command(centreX, flags, centreY, mapLeftRight, subGameCommandType, 4, mapTopBottom);
+	commandType = command == 1 ? GAME_COMMAND_RAISE_LAND : GAME_COMMAND_LOWER_LAND;
+	result = game_do_command(centreX, flags, centreY, mapLeftRight, commandType, 4, mapTopBottom);
 	if (result != MONEY32_UNDEFINED) {
 		totalCost += result;
 	}
@@ -2340,8 +2176,8 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 	mapElement = map_get_surface_element_at(x >> 5, y >> 5);
 	int slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
 	if (slope != 0) {
-		int command = subCommand == 0xFFFF ? GAME_COMMAND_RAISE_LAND : GAME_COMMAND_LOWER_LAND;
-		result = game_do_command(centreX, flags, centreY, mapLeftRight, command, 4, mapTopBottom);
+		commandType = command == 0xFFFF ? GAME_COMMAND_RAISE_LAND : GAME_COMMAND_LOWER_LAND;
+		result = game_do_command(centreX, flags, centreY, mapLeftRight, commandType, 4, mapTopBottom);
 		if (result != MONEY32_UNDEFINED) {
 			totalCost += result;
 		}
@@ -2350,51 +2186,41 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 		y = mapTop;
 		mapElement = map_get_surface_element_at(x >> 5, y >> 5);
 		slope = mapElement->properties.surface.slope & MAP_ELEMENT_SLOPE_MASK;
-
-		*ebx = totalCost * 4;
-		RCT2_GLOBAL(RCT2_ADDRESS_NEXT_EXPENDITURE_TYPE, uint8) = RCT_EXPENDITURE_TYPE_LANDSCAPING * 4;
-		RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_X, uint32) = centreX;
-		RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_Y, uint32) = centreY;
-		RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_Z, uint32) = centreZ;
-		return;
-	}
-
-	x = mapLeft;
-	y = mapTop;
-	int bx = ((mapRight - mapLeft) >> 5) - 1;
-	sint8 byte_F1AD5C = -2;
-
-	for (;;) {
-		byte_F1AD5C += 2;
-		bx += 2;
-		x -= 32;
-		y -= 32;
-		if (bx > 64) {
-			*ebx = totalCost * 4;
+		if (slope != 0) {
 			RCT2_GLOBAL(RCT2_ADDRESS_NEXT_EXPENDITURE_TYPE, uint8) = RCT_EXPENDITURE_TYPE_LANDSCAPING * 4;
 			RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_X, uint32) = centreX;
 			RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_Y, uint32) = centreY;
 			RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_Z, uint32) = centreZ;
-			return;
+			return totalCost * 4;
 		}
+	}
 
-		sint8 minZ = (byte_F1AD5C << 1) & 0xFF;
+	x = mapLeft;
+	y = mapTop;
+	int size = ((mapRight - mapLeft) >> 5) + 1;
+	sint8 initialMinZ = -2;
+
+	for (; size <= 64; size += 2) {
+		initialMinZ += 2;
+		sint8 minZ = (initialMinZ << 1) & 0xFF;
+		x -= 32;
+		y -= 32;
 
 		// Corner (North-West)
 		mapElement = map_get_surface_element_at(mapLeft >> 5, mapTop >> 5);
-		z = map_get_corner_height(mapElement, 4);
-		result = sub_68C3B2(flags, x, y, z, minZ);
+		z = map_get_corner_height(mapElement, 2);
+		result = smooth_land_tile(0, flags, x, y, z, minZ);
 		if (result != MONEY32_UNDEFINED) {
 			totalCost += result;
 		}
 		y += 32;
 
 		// Side (West)
-		for (int i = 0; i < bx; i++) {
+		for (int i = 0; i < size; i++) {
 			int y2 = clamp(mapTop, y, mapBottom);
 			mapElement = map_get_surface_element_at(mapLeft >> 5, y2 >> 5);
-			z = map_get_corner_height(mapElement, 4);
-			result = sub_68C47A(flags, x, y, z, minZ);
+			z = map_get_corner_height(mapElement, 2);
+			result = smooth_land_tile(1, flags, x, y, z, minZ);
 			if (result != MONEY32_UNDEFINED) {
 				totalCost += result;
 			}
@@ -2405,8 +2231,8 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 					minZ += 2;
 				}
 			}
-			z = map_get_corner_height(mapElement, 8);
-			result = sub_68C3B2(flags, x, y, z, minZ);
+			z = map_get_corner_height(mapElement, 3);
+			result = smooth_land_tile(0, flags, x, y, z, minZ);
 			if (result != MONEY32_UNDEFINED) {
 				totalCost += result;
 			}
@@ -2416,19 +2242,19 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 
 		// Corner (South-West)
 		mapElement = map_get_surface_element_at(mapLeft >> 5, mapBottom >> 5);
-		z = map_get_corner_height(mapElement, 8);
-		result = sub_68C47A(flags, x, y, z, minZ);
+		z = map_get_corner_height(mapElement, 3);
+		result = smooth_land_tile(1, flags, x, y, z, minZ);
 		if (result != MONEY32_UNDEFINED) {
 			totalCost += result;
 		}
 		x += 32;
 
 		// Side (South)
-		for (int i = 0; i < bx; i++) {
+		for (int i = 0; i < size; i++) {
 			int x2 = clamp(mapLeft, x, mapRight);
 			mapElement = map_get_surface_element_at(x2 >> 5, mapBottom >> 5);
-			z = map_get_corner_height(mapElement, 8);
-			result = sub_68C222(flags, x, y, z, minZ);
+			z = map_get_corner_height(mapElement, 3);
+			result = smooth_land_tile(2, flags, x, y, z, minZ);
 			if (result != MONEY32_UNDEFINED) {
 				totalCost += result;
 			}
@@ -2439,8 +2265,8 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 					minZ += 2;
 				}
 			}
-			z = map_get_corner_height(mapElement, 1);
-			result = sub_68C47A(flags, x, y, z, minZ);
+			z = map_get_corner_height(mapElement, 0);
+			result = smooth_land_tile(1, flags, x, y, z, minZ);
 			if (result != MONEY32_UNDEFINED) {
 				totalCost += result;
 			}
@@ -2450,19 +2276,19 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 
 		// Corner (South-East)
 		mapElement = map_get_surface_element_at(mapRight >> 5, mapBottom >> 5);
-		z = map_get_corner_height(mapElement, 1);
-		result = sub_68C222(flags, x, y, z, minZ);
+		z = map_get_corner_height(mapElement, 0);
+		result = smooth_land_tile(2, flags, x, y, z, minZ);
 		if (result != MONEY32_UNDEFINED) {
 			totalCost += result;
 		}
 		y -= 32;
 
 		// Side (East)
-		for (int i = 0; i < bx; i++) {
+		for (int i = 0; i < size; i++) {
 			int y2 = clamp(mapTop, y, mapBottom);
 			mapElement = map_get_surface_element_at(mapRight >> 5, y2 >> 5);
-			z = map_get_corner_height(mapElement, 1);
-			result = sub_68C2EA(flags, x, y, z, minZ);
+			z = map_get_corner_height(mapElement, 0);
+			result = smooth_land_tile(3, flags, x, y, z, minZ);
 			if (result != MONEY32_UNDEFINED) {
 				totalCost += result;
 			}
@@ -2473,8 +2299,8 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 					minZ += 2;
 				}
 			}
-			z = map_get_corner_height(mapElement, 2);
-			result = sub_68C222(flags, x, y, z, minZ);
+			z = map_get_corner_height(mapElement, 1);
+			result = smooth_land_tile(2, flags, x, y, z, minZ);
 			if (result != MONEY32_UNDEFINED) {
 				totalCost += result;
 			}
@@ -2484,19 +2310,19 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 
 		// Corner (North-East)
 		mapElement = map_get_surface_element_at(mapRight >> 5, mapTop >> 5);
-		z = map_get_corner_height(mapElement, 2);
-		result = sub_68C2EA(flags, x, y, z, minZ);
+		z = map_get_corner_height(mapElement, 1);
+		result = smooth_land_tile(3, flags, x, y, z, minZ);
 		if (result != MONEY32_UNDEFINED) {
 			totalCost += result;
 		}
 		x -= 32;
 
 		// Side (North)
-		for (int i = 0; i < bx; i++) {
+		for (int i = 0; i < size; i++) {
 			int x2 = clamp(mapLeft, x, mapRight);
 			mapElement = map_get_surface_element_at(x2 >> 5, mapTop >> 5);
-			z = map_get_corner_height(mapElement, 2);
-			result = sub_68C3B2(flags, x, y, z, minZ);
+			z = map_get_corner_height(mapElement, 1);
+			result = smooth_land_tile(0, flags, x, y, z, minZ);
 			if (result != MONEY32_UNDEFINED) {
 				totalCost += result;
 			}
@@ -2507,8 +2333,8 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 					minZ += 2;
 				}
 			}
-			z = map_get_corner_height(mapElement, 4);
-			result = sub_68C2EA(flags, x, y, z, minZ);
+			z = map_get_corner_height(mapElement, 2);
+			result = smooth_land_tile(3, flags, x, y, z, minZ);
 			if (result != MONEY32_UNDEFINED) {
 				totalCost += result;
 			}
@@ -2517,7 +2343,28 @@ void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi,
 		}
 	}
 
-	*ebx = totalCost;
+	RCT2_GLOBAL(RCT2_ADDRESS_NEXT_EXPENDITURE_TYPE, uint8) = RCT_EXPENDITURE_TYPE_LANDSCAPING * 4;
+	RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_X, uint32) = centreX;
+	RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_Y, uint32) = centreY;
+	RCT2_GLOBAL(RCT2_ADDRESS_COMMAND_MAP_Z, uint32) = centreZ;
+	return totalCost * 4;
+}
+
+/**
+ *
+ *  rct2: 0x0068BC01
+ */
+void game_command_smooth_land(int* eax, int* ebx, int* ecx, int* edx, int* esi, int* edi, int* ebp)
+{
+	int flags = *ebx & 0xFF;
+	int centreX = *eax & 0xFFFF;
+	int centreY = *ecx & 0xFFFF;
+	int mapLeft = *edx & 0xFFFF;
+	int mapTop = *ebp & 0xFFFF;
+	int mapRight = *edx >> 16;
+	int mapBottom = *ebp >> 16;
+	int command = *edi;
+	*ebx = smooth_land(flags, centreX, centreY, mapLeft, mapTop, mapRight, mapBottom, command);
 }
 
 /**