Timeline

Port Karifa — Attack on Titan map

Marley's great naval port on the northern coast, and the only anchorage on the continent wide enough to hold a fleet the whole world has contributed to. Yelena named it to Eren a year before the declaration of war: let every nation gather its navy in one harbour, and a partial Rumbling that walks no further than this coast would drown the war they are all coming to fight, and buy the island decades. Karifa is the smaller war Eren was offered. The record of this port is the record of him hearing the plan out, and choosing the other one.