diff --git a/qbsp/test_qbsp.cc b/qbsp/test_qbsp.cc
index 05df966f..09c4e30a 100644
--- a/qbsp/test_qbsp.cc
+++ b/qbsp/test_qbsp.cc
@@ -994,6 +994,8 @@ TEST_CASE("q1_cube", "[testmaps_q1]")
         {80, -144, 112}
     };
 
+    CHECK(bsp.dedges.size() == 13); // index 0 is reserved, and the cube has 12 edges
+
     REQUIRE(7 == bsp.dleafs.size());
 
     // check the solid leaf
@@ -1023,6 +1025,17 @@ TEST_CASE("q1_cube", "[testmaps_q1]")
     CHECK(cube_bounds.grow(-1).maxs() == bsp.dmodels[0].maxs);
 }
 
+/**
+ * Two solid cuboids touching along one edge
+ */
+TEST_CASE("q1_cubes", "[testmaps_q1]")
+{
+    const auto [bsp, bspx, prt] = LoadTestmapQ1("qbsp_q1_cubes.map");
+
+    // index 0 is reserved, and the first cube has 12 edges, the second can share one edge so only needs 11
+    CHECK(bsp.dedges.size() == 24);
+}
+
 /**
  * Ensure submodels that are all "clip" get bounds set correctly
  */
diff --git a/testmaps/qbsp_q1_cubes.map b/testmaps/qbsp_q1_cubes.map
new file mode 100644
index 00000000..9a050e7e
--- /dev/null
+++ b/testmaps/qbsp_q1_cubes.map
@@ -0,0 +1,33 @@
+// Game: Quake
+// Format: Valve
+// entity 0
+{
+"mapversion" "220"
+"classname" "worldspawn"
+"wad" "deprecated/free_wad.wad;deprecated/fence.wad;deprecated/origin.wad;deprecated/hintskip.wad"
+"_wateralpha" "0.5"
+"_tb_def" "builtin:Quake.fgd"
+// brush 0
+{
+( 32 -256 112 ) ( 32 -255 112 ) ( 32 -256 113 ) orangestuff8 [ 0 1 0 -16 ] [ 0 0 -1 0 ] 0 1 1
+( 64 -240 96 ) ( 63 -240 96 ) ( 64 -240 97 ) orangestuff8 [ -1 0 0 16 ] [ 0 0 -1 0 ] 180 1 1
+( 64 -576 80 ) ( 64 -575 80 ) ( 63 -576 80 ) orangestuff8 [ 1 0 0 -16 ] [ 0 -1 0 16 ] 180 1 1
+( -16 -256 112 ) ( -17 -256 112 ) ( -16 -255 112 ) orangestuff8 [ -1 0 0 16 ] [ 0 -1 0 16 ] 180 1 1
+( -16 -144 112 ) ( -16 -144 113 ) ( -17 -144 112 ) orangestuff8 [ 1 0 0 -16 ] [ 0 0 -1 0 ] 180 1 1
+( 80 -576 96 ) ( 80 -576 97 ) ( 80 -575 96 ) orangestuff8 [ 0 -1 0 16 ] [ 0 0 -1 0 ] 0 1 1
+}
+// brush 1
+{
+( -16 -352 112 ) ( -16 -351 112 ) ( -16 -352 113 ) orangestuff8 [ 0 1 0 16 ] [ 0 0 -1 0 ] 0 1 1
+( 16 -336 96 ) ( 15 -336 96 ) ( 16 -336 97 ) orangestuff8 [ -1 0 0 -32 ] [ 0 0 -1 0 ] 180 1 1
+( 16 -672 80 ) ( 16 -671 80 ) ( 15 -672 80 ) orangestuff8 [ 1 0 0 32 ] [ 0 -1 0 -16 ] 180 1 1
+( -64 -352 112 ) ( -65 -352 112 ) ( -64 -351 112 ) orangestuff8 [ -1 0 0 -32 ] [ 0 -1 0 -16 ] 180 1 1
+( -64 -240 112 ) ( -64 -240 113 ) ( -65 -240 112 ) orangestuff8 [ 1 0 0 32 ] [ 0 0 -1 0 ] 180 1 1
+( 32 -672 96 ) ( 32 -672 97 ) ( 32 -671 96 ) orangestuff8 [ 0 -1 0 -16 ] [ 0 0 -1 0 ] 0 1 1
+}
+}
+// entity 1
+{
+"classname" "info_player_start"
+"origin" "56 -208 136"
+}