diff --git a/services/flysim/crates/flybrain-gb/src/pokemon_red/macros/geography.rs b/services/flysim/crates/flybrain-gb/src/pokemon_red/macros/geography.rs
index f32c354..8abc285 100644
--- a/services/flysim/crates/flybrain-gb/src/pokemon_red/macros/geography.rs
+++ b/services/flysim/crates/flybrain-gb/src/pokemon_red/macros/geography.rs
@@ -112,6 +112,14 @@ const LINKS: &[(u8, u8)] = &[
     (maps::VIRIDIAN_FOREST_NORTH_GATE, maps::ROUTE_2),
     (maps::VIRIDIAN_FOREST_NORTH_GATE, maps::VIRIDIAN_FOREST),
     (maps::PEWTER_GYM, maps::PEWTER_CITY),
+    // The museum, both floors. It is on the graph for the same reason the gym is: the rung-10
+    // loop of 2026-09-22 spent its hours on these two maps with `GO OBJECTIVE` off the pad
+    // entirely, because a map with no row here has no neighbours, so `next_hop` answers nothing
+    // and `area_of` answers nothing -- no road to the gym from indoors, and no errand either.
+    // Both rows are the cartridge's own warp table, surveyed from the rung-10 checkpoint: Pewter
+    // City names `$34` at (14, 7) and (19, 5), and `$34` names `$35` at (7, 7).
+    (maps::PEWTER_MUSEUM_1F, maps::PEWTER_CITY),
+    (maps::PEWTER_MUSEUM_2F, maps::PEWTER_MUSEUM_1F),
     (maps::PEWTER_MART, maps::PEWTER_CITY),
     (maps::PEWTER_POKECENTER, maps::PEWTER_CITY),
     (maps::MT_MOON_1F, maps::ROUTE_3),
@@ -551,6 +559,40 @@ mod tests {
         );
     }
 
+    #[test]
+    fn the_museums_two_floors_know_the_road_to_the_gym() {
+        // The rung-10 loop of 2026-09-22: five and a half hours on `PEWTER_CITY` with the
+        // objective two doors away, and inside the museum `GO OBJECTIVE` was off the pad because
+        // the map had no row here at all. Both floors, because the fly spent the run on both.
+        let at = |map: u8| Region::whole(map);
+        assert_eq!(
+            next_hop(at(maps::PEWTER_MUSEUM_1F), maps::PEWTER_GYM),
+            Some(maps::PEWTER_CITY),
+            "the way to the gym from the museum's ground floor is out of its front door"
+        );
+        assert_eq!(
+            next_hop(at(maps::PEWTER_MUSEUM_2F), maps::PEWTER_GYM),
+            Some(maps::PEWTER_MUSEUM_1F),
+            "and from the upper floor it is the staircase"
+        );
+        assert_eq!(next_hop(at(maps::PEWTER_CITY), maps::PEWTER_GYM), Some(maps::PEWTER_GYM));
+        // The other direction, which is what `GO OBJECTIVE` asks when the errand is the museum's
+        // own town: the museum is one hop from Pewter City and two from its upper floor.
+        assert_eq!(
+            next_hop(at(maps::PEWTER_CITY), maps::PEWTER_MUSEUM_2F),
+            Some(maps::PEWTER_MUSEUM_1F)
+        );
+        // And the area, which is what puts the town's errands on the pad indoors. The upper
+        // floor has no area, exactly as `REDS_HOUSE_2F` has none: a floor with no front door of
+        // its own is not "in" anywhere, so it offers no errand -- and the road out is still the
+        // staircase above, which is what the fly needs there.
+        assert_eq!(area_of(maps::PEWTER_MUSEUM_1F), Some(maps::PEWTER_CITY));
+        assert_eq!(area_of(maps::PEWTER_MUSEUM_2F), None);
+        // The museum is neither a mart nor a centre, so it is nobody's errand.
+        assert_eq!(amenity_at(maps::PEWTER_MUSEUM_1F), None);
+        assert_eq!(amenity_at(maps::PEWTER_MUSEUM_2F), None);
+    }
+
     #[test]
     fn a_maps_area_is_its_town_indoors_and_out() {
         // Outdoors a map is its own area, including a route -- which has no amenity row, so it
diff --git a/services/flysim/crates/flybrain-gb/src/pokemon_red/maps.rs b/services/flysim/crates/flybrain-gb/src/pokemon_red/maps.rs
index 986b6f4..fd1b4e8 100644
--- a/services/flysim/crates/flybrain-gb/src/pokemon_red/maps.rs
+++ b/services/flysim/crates/flybrain-gb/src/pokemon_red/maps.rs
@@ -18,6 +18,13 @@
 //! `PEWTER_MART` `$38` and `PEWTER_POKECENTER` `$3a` sit in the five ids between `PEWTER_GYM`
 //! `$36` and `MT_MOON_1F` `$3b`; `CERULEAN_POKECENTER` `$40` and `CERULEAN_MART` `$43` sit around
 //! `CERULEAN_GYM` `$41`. [`super::tests`] pins each against its neighbour rather than on its own.
+//!
+//! **2026-09-22, the rung-10 museum.** `PEWTER_MUSEUM_1F` `$34` and `PEWTER_MUSEUM_2F` `$35` are
+//! the two ids between `VIRIDIAN_FOREST` `$33` and `PEWTER_GYM` `$36`, and both are confirmed by
+//! the cartridge rather than by counting: Pewter City's warp table names `$34` at (14, 7) and at
+//! (19, 5) -- the museum's two doors -- and `$34`'s own warp at (7, 7) names `$35`, which is the
+//! staircase. Surveyed from the release container's rung-10 checkpoint
+//! (`infra/docs/macros-traps.md`, 2026-09-22).
 
 // Outdoors: `$00`..`$24`.
 pub const PALLET_TOWN: u8 = 0x00;
@@ -68,6 +75,8 @@ pub const VIRIDIAN_GYM: u8 = 0x2d;
 pub const VIRIDIAN_FOREST_NORTH_GATE: u8 = 0x2f;
 pub const VIRIDIAN_FOREST_SOUTH_GATE: u8 = 0x32;
 pub const VIRIDIAN_FOREST: u8 = 0x33;
+pub const PEWTER_MUSEUM_1F: u8 = 0x34;
+pub const PEWTER_MUSEUM_2F: u8 = 0x35;
 pub const PEWTER_GYM: u8 = 0x36;
 pub const PEWTER_MART: u8 = 0x38;
 pub const PEWTER_POKECENTER: u8 = 0x3a;