Numazu, city, southeastern Shizuoka ken (prefecture), central Honshu, Japan. It lies at the mouth of the Kano River, facing Suruga Bay, at the base of the Izu Peninsula. It developed as a castle town in the early 16th century and later served as a post town on the Tōkaidō (“Eastern Sea Highway”). Because of the city’s location at the junction of land and sea routes, it became a regional commercial and administrative centre. It industrialized rapidly during the 1960s, and the traditional economic mainstays of fishing and tourism declined in importance. The city’s products now include machinery, photographic film, chemicals, metal, and textiles. Numazu is just south of Mount Fuji, and Fuji-Hakone-Izu National Park stretches southward along the coast of the Izu Peninsula. Numazu Park contains a municipal aquarium and Sembon-matsu (“Thousand-Pines”) Beach, noted for its ancient, gnarled trees. Pop. (2005) 208,001; (2010) 202,304.