diff --git a/src/simulator/crates/mc-city/src/city.rs b/src/simulator/crates/mc-city/src/city.rs
index af005beb..168d00a7 100644
--- a/src/simulator/crates/mc-city/src/city.rs
+++ b/src/simulator/crates/mc-city/src/city.rs
@@ -195,12 +195,12 @@ pub const CITY_CENTER_BASELINE_CULTURE: f64 = 2.0;
 /// reach pop 30 from ~7000 to ~3500 — the dominant lever for pop_peak.
 pub const GROWTH_FOOD_CARRYOVER: f64 = 0.5;
 
-/// Base city HP before population scaling. Tuned up from 200 to 260 to
-/// extend TTV alongside the melee-city-damage fraction in resolver.rs. The
-/// combination (HP boost + 0.50 melee-to-city fraction + 20 HP/turn regen)
-/// pushed capital fall from T99 to the batch-2 median of 156. Further bumps
-/// (280, 300) regressed results — 260 is the empirical peak.
-pub const BASE_CITY_HP: u32 = 260;
+/// Base city HP before population scaling. Bumped 260 → 500 for p1-29 R5a:
+/// prior small bumps (280, 300) regressed because at low HP the snowballer's
+/// stack still one-shots; the handoff calls for a step large enough that
+/// capture takes 5-10 turns of siege rather than 1-2. Composed with the
+/// stronger wall penalty in mc-combat::siege (tier1 0.40, tier2 0.25).
+pub const BASE_CITY_HP: u32 = 500;
 
 /// HP gained per population point.
 pub const HP_PER_POP: u32 = 10;
@@ -1021,7 +1021,7 @@ mod tests {
     #[test]
     fn defense_mechanics() {
         let mut city = City::found("Ironhold", (5, 5), true, 1, None);
-        let initial_hp = BASE_CITY_HP + HP_PER_POP; // 210 at pop 1
+        let initial_hp = BASE_CITY_HP + HP_PER_POP;
         assert_eq!(city.hp, initial_hp);
         city.take_damage(50);
         assert_eq!(city.hp, initial_hp - 50);