American rock band formed in San Francisco, California in 1965. One of the pioneering bands of psychedelic rock, the group defined the San Francisco Sound and was the first from the Bay Area to achieve international commercial success. They headlined the Monterey Pop Festival, Woodstock, Altamont Free Concert, and the first Isle of Wight Festival in England. Their 1967 breakout album Surrealistic Pillow was one of the most significant recordings of the Summer of Love. Two songs from that album, "Somebody to Love" and "White Rabbit", are among Rolling Stone's "500 Greatest Songs of All Time"