In the first years its role was simply to provide fuel and drinking water to any foreign ships that arrived; it was then opened officially in 1859, whereupon land was reclaimed from the coastal Oura area starting in 1860 and the settlement was founded.
この時は、来航する外国船に薪水を供給する程度であったが、1859年本格開放されて1860年から大浦一帯の海岸が埋め立てられ、居留地が造成された。