Organ Pipe Cactus National Monument is a U.S. National Monument and UNESCO biosphere reserve located in extreme southern Arizona which shares a border with the Mexican state of Sonora. The park is the only place in the United States where the Organ Pipe Cactus grows wild. Along with Organ Pipe, many other types of cacti, as well as other desert flora native to the Yuma Desert section of the Sonoran Desert region grow here. The Park is a beautiful preservation of the American Southwest.
Land for the graded through the Monument was donated by the Arizona state legislature to the federal government during Prohibition knowing that the north-south road would be improved and make contraband alcohol easier to import from Mexico. In 1937 the land was officially opened as a national monument.
At the north entrance of the park is the city of Why, Arizona; the town of Lukeville, Arizona, sits at the park's southern border. Lukeville is a border crossing point to Sonoyta, Sonora, Mexico.