The California Quadrangle, California Building, and California Tower are historic structures located in Balboa Park in San Diego, California. They were built for the 1915–16 Panama-California Exposition and served as the grand entry to the Expo. The buildings and courtyard were designed by architect Bertram Goodhue. They were added to the National Register of Historic Places on May 17, 1974. They now house the Museum of Us.
The Quadrangle includes the California Building and Tower on the north side, and Evernham Hall and the St. Francis Chapel on the south side. Between them is an open space linked by arcaded passageways and massive arched gateways to form the Plaza de California. The original Balboa Park Administration Building lies just outside the Quadrangle, adjacent to and west of the California Building. Unlike most of the exhibits at the Expo, the Quadrangle buildings were intended to be permanent.
The Plaza de California is the main entryway to Balboa Park, approached over the Cabrillo Bridge. That entry is currently a two-lane road providing vehicle access to the park.