During World War II, activities at the Yokosuka Navy Yard reached their peak.
By 1944, the Yard covered 280 acres (1.1 km) and employed over 40,000 workers.
Japan is famous for its vivid collection of flora and fauna and Yokosuka is no different.The present-day Yokosuka is one of the oldest inhabitations of Japan, with the historical archives dating back to the paleolithic period and is a perfect blend of cross-cultural exchange between the Japanese and American culture.The port of Yokosuka exists since 1854 when a treaty signed between Japan and the United States allowed the two countries to establish trade routes between them.In 1860, Lord Oguri Kozuke-no-Suke, Minister of Finance to the Tokugawa Shogunate Government, decided that "If Japan is to assume an active role in world trade, she must have proper facilities to build and maintain large seagoing vessels." He called upon the French Consul General, Léon Roches, and asked for the assistance of the French government to build a shipyard and various basing facilities capable of handling large ships.The French engineer Léonce Verny was sent to Japan to accomplish the task. In 1871, the name was changed to the "Yokosuka Navy Yard".