The Palace of Natural History was situated immediately adjacent to the California-Pacific International Exposition's main entrance, on the north side of the Avenida de Palacios. The large Spanish-Renaissance style reinforced-concrete structure, designed by architect William Templeton Johnson, was built on the site of the former Civic Auditorium; known as the Southern California Counties Building during the 1915-16 exposition. After the Civic Auditorium was destroyed by fire in 1925, local philanthropist Ellen Browning Scripps donated the funds necessary to construct the three-level building, which was named the Natural History Museum and opened to the public in 1933. Over 300,000 specimens of wildlife, shells, fossils, minerals, and flora were contained within the spacious structure; in addition to a complete research library and laboratory. The Civilian Conservation Corps also maintained a comprehensive exhibit in the building during the exposition.