The Natural History Museum in Balboa Park was founded as the San Diego Society of Natural History in 1874, originally organized at the Hotel Cecil on 6th Avenue. The society moved the museum to the park in 1917 into a building from the 1915-16 Exposition. They occupied 3 buildings before moving into the current building in 1933, designed by William Templeton Johnson. A major reconstruction in 2001 more than doubled the facility's size. It is the third oldest scientific institution west of the Mississippi and the oldest in Southern California.