City (pop., 2000: 1,223,400) and port, southern California, U.S. It is located on San Diego Bay, the site of major naval and military bases. Sighted by the Spanish in 1542 and named San Miguel, the area was renamed San Diego in 1602. In 1769 the Spanish established a military post on the site, and Junípero Serra dedicated the first California mission there. The U.S. acquired it from Mexico in 1846, and a new city was laid out in 1867. The arrival of the Santa Fe railroad in 1885 stimulated the city's growth. Industrial development is dominated by aerospace, electronics, and shipbuilding, and the city is the main commercial outlet for the farm produce of southern California. Balboa Park and its San Diego Zoo are renowned, as are the area universities.