is one of the 18 ku (wards) of the city of Yokohama in Kanagawa Prefecture, Japan. As of 2010, the ward had an estimated population of 270,433 and a density of 8,140 persons per km². The total area is 33.23 km². Geography Tsurumi-ku is located in eastern Kanagawa Prefecture, in the northeast corner of the city of Yokohama. Surrounding municipalities Kanagawa Ward Kōhoku Ward Kawasaki History The area around present-day Tsurumi Ward has been inhabited continuously for thousands of years. Archaeologists have found stone tools from the Japanese Paleolithic period and ceramic shards from the Jōmon period, and tombs from the Kofun period at numerous locations in the area. Under the Nara period Ritsuryō system, it became part of Musashi Province. During the Edo period, the territory came under the control of Tokugawa Ieyasu. It was administered as tenryō territory controlled directly by the Tokugawa shogunate, but administered through various hatamoto. During the Bakumatsu period, nearby Kanagawa-juku was the location of the signing of the Convention of Kanagawa, which ended Japan’s national isolation policy and led to the normalization of diplomatic relations between the United States and Japan. The subsequent Treaty of Amity and Commerce led to the establishment of a treaty port for foreign commerce and settlement, which was initially stipulated to be Kanagawa. However, for security reasons, the actual settlement was established at neighboring Yokohama (present day Naka-ku). The Namamugi Incident, which led to the 1863 Anglo-Satsuma War, occurred in what is now part of Tsurumi Ward. After the Meiji Restoration, the area was transferred to the new Tachibana District of Kanagawa Prefecture in 1868. Tsurumi was connected to Yokohama and Tokyo by train in 1872, and the area rapidly urbanized. Sōji-ji, the head temple of the Sōtō sect of Zen Buddhism relocated to Tsurumi from Ishikawa Prefecture in 1911. Tsurumi suffered severe damage from the 1923 Great Kantō earthquake. In April 1924, Tsurumi became a town within Tachibana District. On October 1, 1927 Tsurumi became a ward within the city of Yokohama. The area suffered greatly again during World War II, and was completely devastated during the massive Yokohama air raid of May 29, 1945. The area soon rebuilt after the end of the war, assisted by an influx of educational facilities in the 1950s and rapid re-industrialization of the area in the 1950s and 1960s. The Tsurumi railway accident occurred near Tsurumi Station on November 9,