However, the hybridization of folk and rock has been seen as having a major influence on the development of rock music, bringing in elements of psychedelia, and helping to develop the ideas of the singer-songwriter, the protest song and concepts of "authenticity". Psychedelic music's LSD-inspired vibe began in the folk scene, with the New York-based Holy Modal Rounders using the term in their 1964 recording of "Hesitation Blues". The first group to advertise themselves as psychedelic rock were the 13th Floor Elevators from Texas, at the end of 1965; producing an album that made their direction clear, with "The Psychedelic Sounds of the 13th Floor Elevators" the following year. Psychedelic rock particularly took off in California's emerging music scene as groups followed the Byrds from folk to folk rock from 1965. The psychedelic life style had already developed in San Francisco and particularly prominent products of the scene were The Grateful Dead, Country Joe and the Fish, The Great Society and Jefferson Airplane. The Byrds rapidly progressed from purely folk rock in 1966 with their single "Eight Miles High", widely taken to be a reference to drug use. Psychedelic rock reached its apogee in the last years of the decade. The Summer of Love of 1967 was prefaced by the Human Be-In event and reached its peak at the Monterey Pop Festival, the latter helping to make a major American star of Jimi Hendrix. Key recordings included Jefferson Airplane's "Surrealistic Pillow" and The Doors' "Strange Days". These trends climaxed in the 1969 Woodstock festival, which saw performances by most of the major psychedelic acts, but by the end of the decade psychedelic rock was in retreat. The Jimi Hendrix Experience and Cream broke up and many surviving acts moved away from psychedelia into more back-to-basics "roots rock", the wider experimentation of progressive rock, or riff-laden heavy rock. Roots rock is the term now used to describe a move away from what some saw as the excesses of the psychedelic scene, to a more basic form of rock and roll that incorporated its original influences, particularly country and folk music, leading to the creation of country rock and Southern rock. In 1966 Bob Dylan went to Nashville to record the album "Blonde on Blonde". This, and subsequent more clearly country-influenced albums, have been seen as creating the genre of country folk, a route pursued by a number of, largely acoustic, folk musicians.