diff --git a/dat/bigrm-13.lua b/dat/bigrm-13.lua
new file mode 100644
index 000000000..5c9a7d25c
--- /dev/null
+++ b/dat/bigrm-13.lua
@@ -0,0 +1,71 @@
+-- NetHack bigroom bigrm-13.lua	$NHDT-Date: 1652196024 2022/05/10 15:20:24 $  $NHDT-Branch: NetHack-3.7 $:$NHDT-Revision: 1.0 $
+--	Copyright (c) 2026 by Pasi Kallinen
+-- NetHack may be freely redistributed.  See license for details.
+--
+-- Pillars
+
+des.level_init({ style = "solidfill", fg = " " });
+des.level_flags("mazelevel", "noflip");
+
+des.map([[
+---------------------------------------------------------------------------
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+|.........................................................................|
+---------------------------------------------------------------------------
+]]);
+
+local pillar = [[
+---
+| |
+---]];
+
+filters = {
+   function(x, y) return true; end,
+   function(x, y) return (x%2 == 1); end,
+   function(x, y) return (((x+y)%2) == 0); end,
+   function(x, y) return (y%2 == 1); end,
+   function(x, y) return (y%2 == 0); end,
+};
+
+idx = math.random(1, #filters);
+
+for y = 0,2 do
+   for x = 0,6 do
+      if (filters[idx](x, y)) then
+         des.map({ coord = {12 + x*9, 4 + y*5}, map = pillar, contents=function() end });
+      end
+   end
+end
+
+des.region(selection.area(00,00,75,18), "lit");
+des.wallify();
+des.non_diggable();
+
+des.stair("up");
+des.stair("down");
+
+for i = 1,15 do
+   des.object();
+end
+for i = 1,6 do
+   des.trap();
+end
+for i = 1,28 do
+  des.monster();
+end
+
diff --git a/dat/dungeon.lua b/dat/dungeon.lua
index eb6223d66..d90eb9214 100644
--- a/dat/dungeon.lua
+++ b/dat/dungeon.lua
@@ -70,7 +70,7 @@ dungeon = {
             base = 10,
             range = 3,
             chance = 40,
-            nlevels = 12
+            nlevels = 13
          },
          {
             name = "medusa",
diff --git a/doc/fixes3-7-0.txt b/doc/fixes3-7-0.txt
index 59666461d..227ad02e7 100644
--- a/doc/fixes3-7-0.txt
+++ b/doc/fixes3-7-0.txt
@@ -2712,7 +2712,7 @@ menu for what-is command supports /^ and /" to view a list of nearby or whole
 	level visible and remembered traps
 spiders will occasionally spin webs when moving around
 drinking a burning potion of oil will cure being turned into slime
-new bigroom variants, a boulder maze and hexagons
+new bigroom variants, a boulder maze, hexagons, pillars
 vomiting on an altar provokes the deities wrath
 branch stairs have a different glyph, show up in yellow color in tty
 duration of confusion when drinking booze depends upon hunger state
diff --git a/sys/unix/NetHack.xcodeproj/project.pbxproj b/sys/unix/NetHack.xcodeproj/project.pbxproj
index 99cd6d6ac..3139be9b4 100644
--- a/sys/unix/NetHack.xcodeproj/project.pbxproj
+++ b/sys/unix/NetHack.xcodeproj/project.pbxproj
@@ -1570,6 +1570,7 @@
 				"$(NH_DAT_DIR)/bigrm-10.lua",
 				"$(NH_DAT_DIR)/bigrm-11.lua",
 				"$(NH_DAT_DIR)/bigrm-12.lua",
+				"$(NH_DAT_DIR)/bigrm-13.lua",
 				"$(NH_DAT_DIR)/bigrm-2.lua",
 				"$(NH_DAT_DIR)/bigrm-3.lua",
 				"$(NH_DAT_DIR)/bigrm-4.lua",
diff --git a/sys/windows/GNUmakefile b/sys/windows/GNUmakefile
index 0341d4aa9..c964d780c 100644
--- a/sys/windows/GNUmakefile
+++ b/sys/windows/GNUmakefile
@@ -475,7 +475,7 @@ CLEAN_FILE += $(NHLUAH)
 LUALIST = air Arc-fila Arc-filb Arc-goal Arc-loca Arc-strt \
 	asmodeus astral baalz Bar-fila Bar-filb Bar-goal \
 	Bar-loca Bar-strt bigrm-1 bigrm-10 bigrm-11 bigrm-2 \
-	bigrm-12 \
+	bigrm-12 bigrm-13 \
 	bigrm-3 bigrm-4 bigrm-5 bigrm-6 bigrm-7 bigrm-8 \
 	bigrm-9 castle Cav-fila Cav-filb Cav-goal Cav-loca \
 	Cav-strt dungeon earth fakewiz1 fakewiz2 fire \
diff --git a/sys/windows/Makefile.nmake b/sys/windows/Makefile.nmake
index e5a180663..e50f9fb21 100644
--- a/sys/windows/Makefile.nmake
+++ b/sys/windows/Makefile.nmake
@@ -711,6 +711,7 @@ HACKINCL = \
 
 LUA_FILES = $(DAT)asmodeus.lua $(DAT)baalz.lua $(DAT)bigrm-1.lua \
 	$(DAT)bigrm-10.lua $(DAT)bigrm-11.lua $(DAT)bigrm-12.lua \
+	$(DAT)bigrm-13.lua \
 	$(DAT)bigrm-2.lua $(DAT)bigrm-3.lua $(DAT)bigrm-4.lua \
 	$(DAT)bigrm-5.lua $(DAT)bigrm-6.lua $(DAT)bigrm-7.lua \
 	$(DAT)bigrm-8.lua $(DAT)bigrm-9.lua $(DAT)castle.lua \
diff --git a/sys/windows/vs/files.props b/sys/windows/vs/files.props
index 16a62721e..07f3c7421 100644
--- a/sys/windows/vs/files.props
+++ b/sys/windows/vs/files.props
@@ -33,6 +33,7 @@
     <Luafiles Include = "bigrm-10.lua"/>
     <Luafiles Include = "bigrm-11.lua"/>
     <Luafiles Include = "bigrm-12.lua"/>
+    <Luafiles Include = "bigrm-13.lua"/>
     <Luafiles Include = "bigrm-2.lua"/>
     <Luafiles Include = "bigrm-3.lua"/>
     <Luafiles Include = "bigrm-4.lua"/>