National monument, southwestern Arizona, U.S., at the Mexican border. It was established in 1937. With an area of 330,689 acres (133,929 hectares), it preserves segments of the mountainous Sonoran Desert and is named for the organ-pipe cactus. Wildlife includes Gila monsters, antelope, coyotes, and a variety of birds.
Learn more about Organ Pipe Cactus National Monument with a free trial on Britannica.com.
Land for the graded road 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.
Its position on the Mexican border has led to much criminal activity involving illegal immigrants and drug traffic within the park. On August 9, 2002, Ranger Kris Eggle was shot and killed by a suspected Mexican drug smuggler during a US Border Patrol operation. The visitor center has been named in his honor.