Crosby, Stills & Nash is a pioneering folk/rock supergroup formed by David Crosby, Stephen Stills and Graham Nash - refugees from three 1960s bands: The Byrds, Buffalo Springfield, and The Hollies. The band is primarily known for their three-part vocal harmonies. They are strongly associated with the 1969 Woodstock Festival. They are commonly referred to by their initials CSN. The trio's first album, Crosby, Stills & Nash, was released in May 1969 and was an immediate hit, spawning two Top 40 hit singles and receiving key airplay on the new FM radio format. In late summer 1969, the trio expanded to a quartet with Neil Young joining the newly named Crosby, Stills, Nash & Young (commonly referred to by their initials CSNY). User-contributed text is available under the Creative Commons By-SA License and may also be available under the GNU FDL.