diff --git a/src/mapgen/dungeongen.h b/src/mapgen/dungeongen.h
index d2e733f71..35e6beef5 100644
--- a/src/mapgen/dungeongen.h
+++ b/src/mapgen/dungeongen.h
@@ -49,7 +49,8 @@ struct DungeonParams {
 	// 3D noise that determines which c_wall nodes are converted to c_alt_wall
 	NoiseParams np_alt_wall;
 
-	// Number of dungeons generated in mapchunk
+	// Number of dungeons generated in mapchunk. All will use the same set of
+	// dungeonparams.
 	u16 num_dungeons;
 	// Dungeons only generate in ground
 	bool only_in_ground;
@@ -68,11 +69,13 @@ struct DungeonParams {
 	u16 large_room_chance;
 	// Dimensions of 3D 'brush' that creates corridors.
 	// Dimensions are of the empty space, not including walls / floor / ceilng.
+	// Diagonal corridors must have hole width >=2 to be passable.
+	// Currently, hole width >= 3 causes stair corridor bugs.
 	v3s16 holesize;
 	// Corridor length random range
 	u16 corridor_len_min;
 	u16 corridor_len_max;
-	// Diagonal corridors are possible
+	// Diagonal corridors are possible, 1 in 4 corridors will be diagonal
 	bool diagonal_dirs;
 	// Usually 'GENNOTIFY_DUNGEON', but mapgen v6 uses 'GENNOTIFY_TEMPLE' for
 	// desert dungeons.
diff --git a/src/mapgen/mapgen.cpp b/src/mapgen/mapgen.cpp
index 9f17af866..6d5e721ce 100644
--- a/src/mapgen/mapgen.cpp
+++ b/src/mapgen/mapgen.cpp
@@ -889,19 +889,21 @@ void MapgenBasic::generateDungeons(s16 max_stone_y)
 		NoiseParams(-0.4, 1.0, v3f(40.0, 40.0, 40.0), 32474, 6, 1.1, 2.0);
 
 	dp.seed                = seed;
-	dp.num_dungeons        = num_dungeons;
 	dp.only_in_ground      = true;
+	dp.num_dungeons        = num_dungeons;
+	dp.notifytype          = GENNOTIFY_DUNGEON;
 	dp.num_rooms           = ps.range(2, 16);
-	dp.room_size_min       = v3s16(6, 5, 6);
-	dp.room_size_max       = v3s16(10, 6, 10);
-	dp.room_size_large_min = v3s16(10, 8, 10);
-	dp.room_size_large_max = v3s16(18, 16, 18);
-	dp.large_room_chance   = (ps.range(1, 4) == 1) ? 1 : 0;
-	dp.holesize            = v3s16(2, 3, 2);
+	dp.room_size_min       = v3s16(5, 5, 5);
+	dp.room_size_max       = v3s16(12, 6, 12);
+	dp.room_size_large_min = v3s16(12, 6, 12);
+	dp.room_size_large_max = v3s16(16, 16, 16);
+	dp.large_room_chance   = (ps.range(1, 4) == 1) ? 8 : 0;
+	dp.diagonal_dirs       = ps.range(1, 8) == 1;
+	// Diagonal corridors must have 'hole' width >=2 to be passable
+	u8 holewidth           = (dp.diagonal_dirs) ? 2 : ps.range(1, 2);
+	dp.holesize            = v3s16(holewidth, 3, holewidth);
 	dp.corridor_len_min    = 1;
 	dp.corridor_len_max    = 13;
-	dp.diagonal_dirs       = ps.range(1, 12) == 1;
-	dp.notifytype          = GENNOTIFY_DUNGEON;
 
 	// Get biome at mapchunk midpoint
 	v3s16 chunk_mid = node_min + (node_max - node_min) / v3s16(2, 2, 2);