The Acid Tests were a series of parties held by Ken Kesey

Ken Kesey

Kenneth Elton "Ken" Kesey was an American author, best known for his novel One Flew Over the Cuckoo's Nest , and as a counter-cultural figure who considered himself a link between the Beat Generation of the 1950s and the hippies of the 1960s. "I was too young to be a beatnik, and too old to be a...

 in the San Francisco Bay Area

San Francisco Bay Area

The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...

  during the mid 1960s, centered entirely around the use of, experimentation with, and advocacy of, the psychedelic

Psychedelic

The term psychedelic is derived from the Greek words ψυχή and δηλοῦν , translating to "soul-manifesting". A psychedelic experience is characterized by the striking perception of aspects of one's mind previously unknown, or by the creative exuberance of the mind liberated from its ostensibly...

 drug LSD

LSD

Lysergic acid diethylamide, abbreviated LSD or LSD-25, also known as lysergide and colloquially as acid, is a semisynthetic psychedelic drug of the ergoline family, well known for its psychological effects which can include altered thinking processes, closed and open eye visuals, synaesthesia, an...

, also known as "acid."

The name "Acid Test" was coined by Kesey, after the term "acid test

Acid test (gold)

An acid test is any qualitative chemical or metallurgical assay which uses acid; most commonly, and historically, the use of a strong acid to distinguish gold from base metals. Figuratively, acid test is any definitive test for some attribute, e.g...

" used by gold miners in the 1850s. He began throwing parties at his farm at La Honda, California

La Honda, California

La Honda is a census-designated place in southern San Mateo County, California, United States. The population was 928 at the 2010 census. It is located in the Santa Cruz Mountains between Silicon Valley and the Pacific coast of California...

.
He took the parties to public places, and advertised with posters that read, "CAN YOU PASS THE ACID TEST?", and the name was later popularized in Tom Wolfe's

Tom Wolfe

Thomas Kennerly "Tom" Wolfe, Jr. is a best-selling American author and journalist. He is one of the founders of the New Journalism movement of the 1960s and 1970s.-Early life and education:...

 1968 book, The Electric Kool-Aid Acid Test

The Electric Kool-Aid Acid Test

The Electric Kool-Aid Acid Test is a work of literary journalism by Tom Wolfe, published in 1968. Using techniques from the genre of hysterical realism and pioneering new journalism, the "nonfiction novel" tells the story of Ken Kesey and his band of Merry Pranksters...

. Musical performances by the Grateful Dead

Grateful Dead

The Grateful Dead was an American rock band formed in 1965 in the San Francisco Bay Area. The band was known for its unique and eclectic style, which fused elements of rock, folk, bluegrass, blues, reggae, country, improvisational jazz, psychedelia, and space rock, and for live performances of long...

 were commonplace, along with black light

Black light

A black light, also referred to as a UV light, ultraviolet light, or Wood's lamp, is a lamp that emits ultraviolet radiation in the long-wave range, and little visible light...

s, strobe light

Strobe light

A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used as a stroboscope...

s, and fluorescent paint

Blacklight paint

Blacklight ink or blacklight-reactive Ink is ink that glows under a black light, a source of light whose wavelengths are primarily in the ultraviolet. The paint may or may not be colorful under ordinary light...

. The Acid Tests are notable for their influence on the LSD-based counterculture of the San Francisco area and subsequent transition from the beat generation

Beat generation

The Beat Generation refers to a group of American post-WWII writers who came to prominence in the 1950s, as well as the cultural phenomena that they both documented and inspired...

 to the hippie

Hippie

The hippie subculture was originally a youth movement that arose in the United States during the mid-1960s and spread to other countries around the world. The etymology of the term 'hippie' is from hipster, and was initially used to describe beatniks who had moved into San Francisco's...

movement.

• 1965
  • 11/27 Santa Cruz, CA
  • 12/4 San Jose, CA (first performance by The Grateful Dead, previously known as The Warlocks)
  • 12/11 Muir Beach, CA
  • 12/24 Portland, OR

• 1966
  • 1/8 San Francisco, CA (Fillmore)
  • 1/15 Portland, OR
  • 1/21–23 San Francisco (Trips Festival at Longshoreman's Hall)
  • 1/29 San Francisco, CA (Sound City Studios)
  • 2/5 Los Angeles, CA (Northridge, Unitarian Church)
  • 2/12 Los Angeles, CA (Watts) – Youth Opportunities Center
  • 2/25 Los Angeles, CA (Hollywood) – Cinema Theatre
  • 3/19 Los Angeles, CA (Pico)Carthay Studios
  • 3/25 Los Angeles, CA (Sunset Strip) – Troupers Club
  • 9/30 – 10/2 San Francisco, CA (San Francisco State) – Whatever It Is Festival – 3 Days
  • 10/31 San Francisco, CA (Acid Test Graduation)