diff --git a/doc/fixes37.0 b/doc/fixes37.0
index 4eec2daf9..8fadd8e14 100644
--- a/doc/fixes37.0
+++ b/doc/fixes37.0
@@ -619,6 +619,9 @@ similar "The ogre lord yanks Cleaver from your corpses!" due to caching the
 	next item, to avoid churning through the whole pool of obufs
 gas clouds are a little random in how they spread out from a point
 Izchak occasionally stocks wands/scrolls/spellbooks of light
+data tracking for #overview was mis-using u.urooms[] and after being in a
+	situation where hero was in multiple rooms at once, visiting other
+	levels might flag unvisisted rooms as having been visited
 
 
 Fixes to 3.7.0-x Problems that Were Exposed Via git Repository
diff --git a/src/dungeon.c b/src/dungeon.c
index 5738a36a5..6d536cc83 100644
--- a/src/dungeon.c
+++ b/src/dungeon.c
@@ -2765,6 +2765,7 @@ recalc_mapseen(void)
     struct trap *t;
     unsigned i, ridx, atmp;
     int x, y, ltyp, count;
+    char uroom;
 
     /* Should not happen in general, but possible if in the process
      * of being booted from the quest.  The mapseen object gets
@@ -2816,18 +2817,14 @@ recalc_mapseen(void)
     /* flags.msanctum, .valley, and .vibrating_square handled below */
 
     /* track rooms the hero is in */
-    for (i = 0; i < SIZE(u.urooms); ++i) {
-        if (!u.urooms[i])
-            continue;
-
-        ridx = u.urooms[i] - ROOMOFFSET;
+    for (i = 0; (uroom = u.urooms[i]) != '\0'; ++i) {
+        ridx = (unsigned) uroom - ROOMOFFSET;
         mptr->msrooms[ridx].seen = 1;
         mptr->msrooms[ridx].untended =
             (g.rooms[ridx].rtype >= SHOPBASE)
-                ? (!(mtmp = shop_keeper(u.urooms[i])) || !inhishop(mtmp))
+                ? (!(mtmp = shop_keeper(uroom)) || !inhishop(mtmp))
                 : (g.rooms[ridx].rtype == TEMPLE)
-                      ? (!(mtmp = findpriest(u.urooms[i]))
-                         || !inhistemple(mtmp))
+                      ? (!(mtmp = findpriest(uroom)) || !inhistemple(mtmp))
                       : 0;
     }