"Eight Miles High" is a song by the American rock band The Byrds, written by Gene Clark, Jim McGuinn (a.k.a. Roger McGuinn), and David Crosby and first released as a single on March 14, 1966 (see 1966 in music). The single managed to reach the Top 20 of the Billboard Hot 100 and the Top 30 of the UK Singles Chart. The song was also included on the band's third album, Fifth Dimension, released on July 18, 1966. "Eight Miles High" became The Byrds' third and final U.S. Top 20 hit, and also their last release before the departure of Gene Clark, who was the band's principal songwriter at the time.