Action scene featuring a fireball explosion at Old Tucson, a movie studio and theme park just west of Tucson, Arizona. Built in 1939 for the movie "Arizona" in 1940, it has been used for the filming of several movies and television westerns since. They include "Gunfight at the O.K. Corral," "Rio Bravo," and the "Little House on the Prairie" TV series of the 1970s-1980s. The attraction was opened to the public in 1960. Photo by Carol Highsmith.