地狱难度。双盆地被群山牢牢隔绝，单纯填海造陆无法开辟有效对外通路。
你可以修建跨山大桥飞跃矿山实现突围，但高山长陡坡会带来重载降速、列车拥堵的沉重物流代价。当工业实力足够，也可爆破山体开凿平缓地面通道，获得永久通畅的运输线路。
Hell difficulty. Twin basins are locked off by massive mountain ranges. Land reclamation alone will not grant you a viable outward route.
You may build large mountain‑spanning bridges to break the containment. Be warned, steep mountain gradients cause heavy cargo slow‑downs and severe train congestion. Once your industry matures, blast through mountain ridges to build flat, permanent ground rail passages.