Yokosuka, a seaport and naval station of Japan, on the W. shore of Tokyo Bay, 12 m. S. of Yokohama. The town is connected by a branch line with the main railway from Tokyo. The port is sheltered by hills and affords good anchorage. The site was occupied by a small fishing village until 1865, when the shogun's government established a shipyard here. In 1868 the Japanese government converted the shipyard into a naval dockyard, and subsequently carried out many improvements. In 1884 the port became a first-class naval station; and naval barracks, warehouses, offices, hospitals, &c., were established here. The dockyard was first constructed by French engineers; but after 1875 the work passed entirely into the hands of Japanese engineers.