diff --git a/server/src/nest/maps/maps.service.ts b/server/src/nest/maps/maps.service.ts
index cc5bd15c3..f2666f1f4 100644
--- a/server/src/nest/maps/maps.service.ts
+++ b/server/src/nest/maps/maps.service.ts
@@ -1,4 +1,5 @@
 import { Injectable } from '@nestjs/common';
+import { isOutsideChina } from '@trek/shared';
 import type {
   MapsSearchResult,
   MapsAutocompleteResult,
@@ -2819,7 +2820,9 @@ export class MapsService {
     lang?: string,
     opts?: { lane?: GeoLane; timeoutMs?: number; locality?: boolean },
   ): Promise<{ name: string | null; address: string | null }> {
-    // Amap answers first when it holds the keyed slot. Resolved at userId 0,
+    // Amap answers first when it holds the keyed slot, and only for a point it
+    // can possibly know: outside its box the call would cost a round trip to
+    // come back empty before Nominatim is asked anyway. Resolved at userId 0,
     // because most callers here have no person behind them (a booking import,
     // an Atlas tile, a right-click on a shared map): the chain stops at the
     // operator env var and the instance-wide row, and nobody's personal key is
@@ -2829,7 +2832,7 @@ export class MapsService {
     if (amap) {
       const latNum = Number.parseFloat(lat);
       const lngNum = Number.parseFloat(lng);
-      if (Number.isFinite(latNum) && Number.isFinite(lngNum)) {
+      if (Number.isFinite(latNum) && Number.isFinite(lngNum) && !isOutsideChina(latNum, lngNum)) {
         try {
           const answer = await amap.reverse(latNum, lngNum, lang);
           if (answer) return answer;
diff --git a/server/tests/unit/nest/maps.amap.test.ts b/server/tests/unit/nest/maps.amap.test.ts
index 022448616..dc3a26664 100644
--- a/server/tests/unit/nest/maps.amap.test.ts
+++ b/server/tests/unit/nest/maps.amap.test.ts
@@ -462,12 +462,15 @@ describe('parseAmapUrl', () => {
 
 // ── Provider selection ───────────────────────────────────────────────────────
 
+/** The user row resolveApiKey reads, with both key columns on it. */
+type KeyRow = { maps_api_key: string | null; amap_api_key: string | null };
+
 /** Make the Google key chain answer, the Amap chain answer, or neither. */
 function keys(opts: { google?: string; amap?: string }) {
-  mockDbGet.mockImplementation((..._args: unknown[]) => {
+  mockDbGet.mockImplementation((..._args: unknown[]): KeyRow => {
     // resolveApiKey reads the caller's own row per name; the SQL differs but
     // the stub only sees the bound userId, so answer both columns at once.
-    return { maps_api_key: opts.google ?? null, amap_api_key: opts.amap ?? null } as any;
+    return { maps_api_key: opts.google ?? null, amap_api_key: opts.amap ?? null };
   });
 }
 
@@ -610,22 +613,35 @@ describe('MapsService with Amap in the keyed slot', () => {
     mockProviderGet.mockReturnValue({ value: 'amap' });
     mockInstanceGet.mockReturnValue({ value: 'akey' });
     const errorSpy = vi.spyOn(console, 'error').mockImplementation(() => {});
-    vi.stubGlobal(
-      'fetch',
-      vi
-        .fn()
-        .mockResolvedValueOnce(amapError('10003'))
-        .mockResolvedValueOnce({ ok: true, json: async () => ({ name: '某处', display_name: '某地址' }) }),
-    );
+    const fetchSpy = vi
+      .fn()
+      .mockResolvedValueOnce(amapError('10003'))
+      .mockResolvedValueOnce({ ok: true, json: async () => ({ name: '某处', display_name: '某地址' }) });
+    vi.stubGlobal('fetch', fetchSpy);
 
     const answer = await svc.reverseGeocode('39.9', '116.4');
     expect(answer).toEqual({ name: '某处', address: '某地址' });
-    const calls = (globalThis.fetch as any).mock.calls.map((c: unknown[]) => String(c[0]));
+    const calls = fetchSpy.mock.calls.map(call => String(call[0]));
     expect(calls[0]).toContain('/v3/geocode/regeo');
     expect(calls[1]).toContain('nominatim');
     errorSpy.mockRestore();
   });
 
+  it('AMAP-082b: a point outside the Amap box goes straight to Nominatim', async () => {
+    // Lisbon. Amap holds the slot, but it knows nothing out here, so asking it
+    // buys a round trip and an empty answer before the fallback runs anyway.
+    mockProviderGet.mockReturnValue({ value: 'amap' });
+    mockInstanceGet.mockReturnValue({ value: 'akey' });
+    const fetchSpy = vi.fn().mockResolvedValue({ ok: true, json: async () => ({ name: 'Belém', display_name: 'Lisboa' }) });
+    vi.stubGlobal('fetch', fetchSpy);
+
+    const answer = await svc.reverseGeocode('38.6916', '-9.2160');
+
+    expect(answer).toEqual({ name: 'Belém', address: 'Lisboa' });
+    expect(fetchSpy).toHaveBeenCalledTimes(1);
+    expect(String(fetchSpy.mock.calls[0][0])).toContain('nominatim');
+  });
+
   it('AMAP-083: a pasted Amap marker link resolves without touching the Google path', async () => {
     // Auto with no key at all: the address comes from Nominatim, the coordinate
     // and the name from the link itself, already converted to WGS-84.