diff --git a/src/games/blockilization/server.ts b/src/games/blockilization/server.ts
index c1da412..b9364b3 100644
--- a/src/games/blockilization/server.ts
+++ b/src/games/blockilization/server.ts
@@ -496,12 +496,19 @@ function begin(game: GameContext, g: Game, withSeats: LobbySeat[]) {
   sendLobby(game);
 }
 
-/** The map's ground is loaded on the server: a point every chunk across it (an unloaded one collides). */
-function mapLoaded(game: GameContext, g: Game): boolean {
+/**
+ * Where the map's ground isn't loaded on the server yet, if anywhere: a point every chunk across it
+ * (an unloaded one collides). Null: all of it is.
+ */
+function unloadedSpot(game: GameContext, g: Game): { x: number; z: number } | null {
   const size = extent(g.grid);
   // (Its last column is just inside: a world that wraps ends at a chunk's edge.)
-  for (let x = 0; x < size.w + 16; x += 16) for (let z = 0; z < size.d + 16; z += 16) if (game.world.collisionHeight(Math.min(x, size.w - 0.5), SEA_Y + 100, Math.min(z, size.d)) > 0) return false;
-  return true;
+  for (let x = 0; x < size.w + 16; x += 16)
+    for (let z = 0; z < size.d + 16; z += 16) {
+      const at = { x: Math.min(x, size.w - 0.5), z: Math.min(z, size.d) };
+      if (game.world.collisionHeight(at.x, SEA_Y + 100, at.z) > 0) return at;
+    }
+  return null;
 }
 
 /** Somewhere far off: screens looking there let the map's ground go. */
@@ -1555,7 +1562,15 @@ export default defineServer(shared, {
       const size = extent(civGame.grid);
       const middle = { x: size.w / 2, y: SEA_Y + 40, z: size.d / 2 };
       if (stage === 'gather') {
-        if (!mapLoaded(game, civGame)) return;
+        // The server loads the world round where people are, 12 chunks at most: a map wider than that
+        // (the large Earth's 14 from its middle) is loaded by taking them to its far parts in turn,
+        // which stay loaded once made. Then back to the middle.
+        const spot = unloadedSpot(game, civGame);
+        if (spot) {
+          for (const p of humans(game)) p.teleport({ x: spot.x, y: SEA_Y + 40, z: spot.z });
+          return;
+        }
+        for (const p of humans(game)) p.teleport(middle);
         stage = 'away';
         stageAt = game.clock.now;
         for (const p of humans(game)) lookAt(p, awayFrom(middle));
diff --git a/tests/headless/blockilization-build.ts b/tests/headless/blockilization-build.ts
new file mode 100644
index 0000000..42ee05d
--- /dev/null
+++ b/tests/headless/blockilization-build.ts
@@ -0,0 +1,38 @@
+import { readFileSync } from 'node:fs';
+import { GameHost } from '../../src/platform/host/game';
+import type { Game } from '../../src/games/blockilization/rules/state';
+import { extent } from '../../src/games/blockilization/geometry';
+import { check, games } from './_harness';
+import { devGames } from '../../src/games/server';
+
+/**
+ * Blockilization builds every map, the widest too: the server loads the world 12 chunks round its
+ * people at most (as far as a screen asks), and the large Earth reaches 14 from its middle, so the
+ * build takes them to its far parts first. (It waited at 0% for them, for good, before.)
+ */
+export default async function blockilizationBuild() {
+  const def = [...games, ...(await devGames())].find((g) => g.id === 'blockilization')!;
+  for (const size of ['large', 'huge'] as const) {
+    // (As in a room: 8 columns round each person, raised to what their screens ask, a few columns a tick.)
+    const host = new GameHost(def, { engine: readFileSync('engine/pkg/voxel_engine_bg.wasm'), seed: 3, remote: true, radius: 8, cheats: true, player: { id: 'p1', name: 'Player' } });
+    const civ = (globalThis as unknown as { __civ: { game: () => Game | null; phase: () => string } }).__civ;
+    const step = (seconds: number) => {
+      for (let t = 0; t < seconds; t += 1 / 30) host.step(1 / 30);
+    };
+    const send = (id: string, name: string, data: unknown) => {
+      host.command(id, { t: 'message', msg: { t: 'game', player: id, name, data } });
+      step(2 / 30);
+    };
+    const ann = host.connect('Ann');
+    host.command(ann.id, { t: 'start' });
+    host.command(ann.id, { t: 'radius', columns: 12 });
+    step(0.5);
+    send(ann.id, 'lobby', { a: 'settings', type: 'earth', size, cityStates: 4 });
+    send(ann.id, 'lobby', { a: 'bots', count: 7 });
+    send(ann.id, 'lobby', { a: 'start' });
+    for (let i = 0; i < 240 && civ.phase() !== 'playing'; i++) step(0.5);
+    const across = extent(civ.game()!.grid).w / 32;
+    check(across > 12, `the ${size} Earth is wider than the server loads round one place (${across} chunks from its middle)`);
+    check(civ.phase() === 'playing', `the ${size} Earth is built and the game begins (${civ.phase()})`);
+  }
+}