Furthur is a 1939 International Harvester school bus purchased by author Ken Kesey in 1964 to carry his "Merry Band of Pranksters" cross-country, filming their counterculture adventures as they went.

Kesey traveled to New York City in November 1963 with his wife Faye and Prankster George Walker to attend the Broadway opening of One Flew Over the Cuckoo's Nest, which was based on his 1962 novel.

He needed to return to New York City in 1964 for the publication party for his novel Sometimes a Great Notion, and hoped to use the occasion to visit the Fair.

Cathy Casamo, friend of Mike Hagen, joined at the last minute, hoping to star in the movie they were supposedly making, but she was left behind in Houston.

Jane Burton, George Walker, Steve Lambrecht, Paula Sundsten (Gretchen Fetchin), Sandy Lehmann-Haupt (sound engineer, younger brother of Christopher, and important source for Tom Wolfe's account [2]), Page Browning, Ron Bevirt (photographer and bookstore owner), and siblings Chuck Kesey, Dale Kesey, and John Babbs are also named as participants.

The group decided to dress in red, white, and blue stripes (so they could claim to be loyal patriots), maybe with distinctive patterns so they'd be easier for future film-goers to tell apart.

Kesey had a generous supply of the then-legal psychedelic drug LSD, and they reportedly also took 500 Benzedrine pills (speed), and a shoebox full of rolled marijuana cigarettes.

They spent two days at Ken Babbs' home in San Juan Capistrano, painting his swimming pool (one version claims he joined at that point.)

Casamo apparently took too much LSD in Wikieup, and spent much of the drive from Phoenix to Houston standing naked on the rear platform, to the amusement of the truckers following Furthur down the highway.

Casamo's antics led to her being briefly institutionalized, so the Pranksters left her behind, and another friend drove her back home (Kesey's Further Inquiry wrestles with his enduring guilt about these events.)

Their next destination was Pensacola, Florida to visit a friend of Babbs, then up the east coast to New York City, arriving around June 29.

Kesey and Babbs took on the frustrating challenge of editing over 100 hours of silent film footage and separate (unsynchronized) audio tapes.

[4] They previewed their progress at regular open parties every weekend at Kesey's place, evolving into the 'Acid Tests' with live music from the Grateful Dead (known first as the Warlocks).

Other Furthur trips included an anti-Vietnam war rally in 1966 and Woodstock and Texas International Pop Festivals, both in 1969 (without Kesey).

More can be read about the adventures of the Merry Pranksters on Furthur in Tom Wolfe's 1968 book The Electric Kool Aid Acid Test, for which a movie directed by Gus Van Sant is in development.

[6][7][8] The original 1964 Furthur was eventually dragged out of the swamp with a tractor and now resides in a warehouse at Kesey's farm in Oregon, alongside the 1990 Further.

[16][17] The cross-country trip of Furthur and the activities of the Merry Pranksters, with the success of Wolfe's book and other media accounts, led to a number of psychedelic buses appearing in popular media over the next few years, including in the Beatles' Magical Mystery Tour (1967 film), Medicine Ball Caravan (1971) and The Muppet Movie (1979 film).

The bus also figures obliquely as a "technicolor motor home" in the Steely Dan song "Kid Charlemagne" (1976), about another LSD proponent, Owsley Stanley.