Hallucinogenic drugs have been around for centuries, but the mid-'60s brought a new wave of experimentation as counterculture movements spread across the world.

In San Francisco, the Grateful Dead enlightened audiences as they joined forces with Ken Kesey and his famous Acid Tests. "The first time I dropped acid was on Jerry [Garcia]'s birthday in 1965," Dead guitarist Bob Weir later told Jas Obrecht. "Even then, the inner quest was what it was about for us."

Meanwhile, across the Atlantic, the Beatles were exploring their own limits of reality with acid. "There's something disturbing about it," Paul McCartney said in Many Years From Now. "You ask yourself, 'How do you come back from it? How do you then lead a normal life after that?' And the answer is, you don't."

These otherworldly experiences often got the creative juices flowing. We're taking a look at the Top 20 LSD songs below. Turn on, tune in and drop out.

20. Tom Petty, "Girl on LSD"
From: B-Side Single (1994)

Tom Petty's "Girl on LSD" was a jaunty tongue-in-cheek tune that ran the gamut of drugs — some legal, some not — from marijuana to meth, cocaine to caffeinated coffee. There's a whole verse for acid, too. "I was in love with a girl on LSD / She'd see things I'd never see," Petty sang. "She broadened her perspective / Then I got more selective / I was in love with a girl on LSD." (Allison Rapp)


19. The Grateful Dead, "Alice. D. Millionaire"
From: The Grateful Dead expanded reissue (2001)

There is no band more closely associated with LSD than the Grateful Dead. When the group first got involved with Ken Kesey's Acid Tests, they weren't concerned about landing a record deal or becoming international stars. "We didn't really care whether we went somewhere specifically," Jerry Garcia said in 1988. "We mostly wanted to have fun, and when we fell in with the acid tests we started having the most fun we'd ever had ever." It was around this time that the band penned "Alice D. Millionaire," a song based on the headline of a San Francisco Chronicle article that announced the bust of casual LSD chemist and Dead sound engineer Owsley Stanley: "LSD Millionaire Arrested." (Rapp)


18. The Beatles, "Sgt. Pepper's Lonely Hearts Club Band"
From: Sgt. Pepper's Lonely Hearts Club Band (1967)

With its trippy sounds, colorful imagery and experimental recording techniques, you could easily argue every song from the Beatles’ Sgt. Pepper's Lonely Hearts Club Band album deserves a spot on this list. The title track gets specific attention because of its backstory. Paul McCartney had continually turned down John Lennon and George Harrison’s attempts to get him to try LSD. When he finally relented, McCartney’s mind opened to broader possibilities of what the Beatles could be. The mindset later helped him concoct the idea of an alter-ego for the group. (Corey Irwin)


17. Talking Heads, "And She Was"
From: Little Creatures (1985)

The Little Creatures album was a milestone moment, with David Byrne bringing in song demos of his ideas for the first time. The origins of “And She Was” were just as warped as the sonic framework of the Talking Heads track itself, which sounded altered. As Byrne later detailed in liner notes for the Once in a Lifetime box set, “And She Was” was inspired by a girl he knew in Baltimore. “She once told me that she used to do acid and lay down on the field by the Yoo-hoo chocolate soda factory,” he wrote. Flying out of her body, he mused, “seemed like such a tacky kind of transcendence – but it was real!” (Matt Wardlaw)


16. The Beach Boys, "California Girls"
From: Summer Days (And Summer Nights!!) (1965)

Anyone surprised to see this wholesome summer classic on our list is probably unfamiliar with the creation of “California Girls.” Music for the Beach Boys’ hit was written by Brian Wilson after his first LSD trip. The experience didn’t go well for Wilson, who reportedly saw images of his parents and was stricken by fear. But when he walked over to his piano, something else came to mind. “I was thinking about the music from cowboy movies,” he told the Los Angeles Times, “and I sat down and started playing it, bum-buhdeeda, bum-buhdeeda. I did that for about an hour. I got these chords going. Then I got this melody, it came pretty fast after that.” (Irwin)


15. The Beatles, "I Want to Tell You"
From: Revolver (1966)

George Harrison was never shy about his LSD use. He once described the first time he took the drug as “like gaining hundreds of years of experience in 12 hours,” and later credited LSD for bringing him to a “whole other consciousness.” “I Want to Tell You” was inspired by the psychedelic’s ability to open someone’s mind. In his autobiography, Harrison noted that the lyrics were the result of “the avalanche of thoughts that are so hard to write down or say or transmit” while taking the drug. (Irwin)


14. The Guess Who, "Undun"
From: Canned Wheat (1969)

“Undun” sheds light on the dark side of the psychedelic drug boom in sublime detail. Inspired by a lyric in Bob Dylan’s “Ballad in Plain D” (“She was easily undone”), Randy Bachman supposedly wrote the song after seeing a woman fall into a coma after dropping acid at a party. Burton Cummings’ vocals drip with anguish as he warns against searching for truth in all the wrong places, and his nimble flute solo is the icing on the cake of Bachman’s breezy, melancholy masterpiece. (Bryan Rolli)


13. The Beatles, "It's All Too Much"
From: Yellow Submarine (1969)

George Harrison penned “It’s All Too Much” during the Summer of Love, fusing his experiences on LSD with Indian musical influences. “‘It’s All Too Much’ was written in a childlike manner from realizations that appeared during and after some LSD experiences and which were later confirmed in meditation,” he later explained. “I just wanted to write a rock ‘n’ roll song about the whole psychedelic thing of the time – because you’d trip out, you see, on all this stuff and then whoops! You’d just be back having your evening cup of tea!” “It’s All Too Much” was recorded after the Beatles completed Sgt. Pepper's Lonely Hearts Club Band and instead appeared on the soundtrack to Yellow Submarine. (Irwin)


12. The Beatles, "I Am the Walrus"
From: Magical Mystery Tour (1967)

After learning that literature classes at his former high school were dedicated to high-level analysis of his lyrics, John Lennon decided to thwart their scholarly pursuits by combining three unrelated lyrical fragments into a deliberately incomprehensible stew. Two LSD trips helped him further muddy the waters. "The first line was written on one acid trip one weekend. The second line was written on the next acid trip the next weekend, and it was filled in after I met Yoko [Ono]," Lennon told Playboy in 1980. His former Quarrymen bandmate Pete Shotten helped by recalling the "yellow matter custard / dead dog's eye" sections from a nursery rhyme the pair used to sing at the playground. Beatles biographer Hunter Davies was present for this joint songwriting session, and recalled Lennon's satisfaction with the results in the 1968 book The Beatles: "Let the fuckers work that one out, Pete!" (Matthew Wilkening)


11. The Rolling Stones, "Jumping Jack Flash"
From: 1968 Single

Unlike a number of songs on this list, the Rolling Stones' "Jumpin' Jack Flash" is actually about trying to distance oneself from LSD. They'd just released Their Satanic Majesties Request, an acid-infused album often compared to the Beatles' Sgt. Pepper's Lonely Hearts Club Band. "I think we were just taking too much acid," Mick Jagger told Rolling Stone in 1995. "We were just getting carried away, just thinking anything you did was fun and everyone should listen to it." "Jumpin' Jack Flash" was an attempt to get back to grittier rock 'n' roll. "It's about having a hard time and getting out," Jagger added. "Just a metaphor for getting out of all the acid things." (Rapp)


10. The 13th Floor Elevators, "Roller Coaster"
From: The Psychedelic Sounds of the 13th Floor Elevators (1966)

If there was a group that was profoundly driven by LSD, it was the 13th Floor Elevators. Producer Bill Bentley and future ZZ Top mastermind Billy Gibbons went to see the Austin, Texas, band frequently as teens. Bentley said their songs went “beyond music,” mostly “because they were on LSD almost every time they played.” Meanwhile, the 13th Floor Elevators inspired Gibbons to form his group, the Moving Sidewalks. “Elevators go up, sidewalks move forward, so it was a match made in heaven,” he later told ABC Audio. “Roller Coaster” demonstrates the intriguing nature of the 13th Floor Elevators’s approach to song structure, with staccato instrumental patterns rising and falling throughout the tune, just like your favorite carnival ride. (Wilkening)


9. Strawberry Alarm Clock, "Incense and Peppermints"
From: Incense and Peppermints (1967)

The members of Strawberry Alarm Clock disliked the lyrics to "Incense and Peppermints" so much that they had a friend sing it instead. The song went to No. 1 and became a central part of 1967's Summer of Love scene. The California band – which included future Lynyrd Skynyrd guitarist Ed King – had been around only a short time when 16-year-old Greg Munford stepped behind the mic for their only Top 10 hit. Over the years, "Incense and Peppermints" has turned into a musical shorthand for all things trippy and druggy from the era (see: Austin Powers: International Man of Mystery). (Michael Gallucci)


8. The Who, "The Acid Queen"
From: Tommy (1969)

Pete Townshend has previously explained that "The Acid Queen" is less about the physical drug itself, and more about how society tends to force indulgence and excess onto ordinary people, even when they aren't interested in it. "Gather your wits and hold them fast," Townshend sings, "your mind must learn to roam." "The Acid Queen" arrives at the point in Tommy when the main character is prodded to partake in the drug, with the hope that it will cure his ailments. It's followed by "Underture," a 10-minute long instrumental that illustrates Tommy's visions and hallucinations. (Rapp)


7. Funkadelic, "Maggot Brain"
From: Maggot Brain (1971)

Guitarist Eddie Hazel’s work on “Maggot Brain” plays out like he was in the midst of the saddest day of his life when he was recording it. The mournful tone of his solo was no accident. George Clinton told Hazel “to play like his mother had died, to picture that day, what he would feel.” As Clinton recalled in his memoir, they were both tripping on acid and his coaching – though extreme – worked like a charm. Hazel’s solo anchored the finished song, which became the title track to Funkadelic’s third album. But more than that, it provided an important moment in Clinton’s view: “It was maybe the first time our emotional ability as artists matched our technical ability as players.” (Wardlaw)


6. Pink Floyd, "Astronomy Domine"
From: The Piper at the Gates of Dawn (1967)

When you get right down to it, Pink Floyd's 1967 debut is basically a 42-minute-long acid trip. Its opening track sets the tone: spaced-out sounds woven between Syd Barrett and Richard Wright's intertwined vocals with pulsating beeps somewhere between a heartbeat and extraterrestrial contact: "Lime and limpid green, a second scene now fights between the blue you once knew." It's the birth of space rock, even if that space is mostly in your head. "Astronomy Domine" would gain even more heft onstage over the years, as the song doubled in size when Pink Floyd took it on more expansive trips. (Gallucci)


5. The Doors, "The End"
From: The Doors (1967)

The Doors had already been performing "The End," an epic song complete with an Oedipal poem in the middle of it, at live shows before they went to record it. To help summon the necessary energy, Jim Morrison dropped acid and the band only did two takes of the track. The recording session might have ended there, but Morrison's trip was only just beginning. "The rest of us left," guitarist Robby Krieger told Rolling Stone, "but he snuck back into the studio and got pissed off that there was no one else around, so he sprayed the place down with a foaming fire extinguisher." (Rapp)


4. The Jimi Hendrix Experience, "Purple Haze"
From: 1967 Single

Jimi Hendrix cited Philip Jose Farmer’s 1966 science-fiction novel Night of Light (in which a faraway planet is engulfed in a reality-altering “purplish haze” every seven years) as the inspiration for this song, claiming he had a dream where he was enveloped in a similar plume and escaped through his faith in Jesus. (An early draft including the phrase “Purple Haze – Jesus Saves” was nixed.) Yet even if the single has nothing to do with LSD, it became a defining song of the psychedelic era thanks to its brain-scrambling lyrics and incendiary six-string racket. You’d be hard-pressed to find a better aural equivalent of a bad trip than the dissonant, tritonal interval used in the legendary opening riff from “Purple Haze.” (Rolli)


3. The Beatles, "She Said She Said"
From: Revolver (1966)

Actor Peter Fonda got himself ejected from an acid-tripping party with the Beatles and the Byrds for committing the cardinal sin of being uncool. George Harrison was convinced he was dying, and Fonda thought it appropriate to comfort him by recounting the story of his self-inflicted childhood gunshot wound, repeatedly telling Harrison, “I know what it’s like to be dead.” John Lennon finally demanded he cut it out, asking Fonda, “Who put all that shit in your head?” He later claimed the actor was “making me feel like I've never been born.” If the incident was traumatic, it at least birthed one of the Beatles’ most inventive songs to date, full of scalding guitar riffs and rapidly shifting time signatures that evoke the creative chaos of that fateful party. (Rolli)


2. Jefferson Airplane, "White Rabbit"
From: Surrealistic Pillow (1967)

Grace Slick wrote a wonderfully warped version of a classic children's story after spending 24 straight hours listening to Miles Davis' Sketches of Spain while on LSD. "White Rabbit" was meant to be a rebuke to parents who read their offspring thinly-veiled stories about drug trips, then get surprised when those children grew up and experimented with psychedelics. "In all those stories, you take some kind of chemical and have a great adventure,” she explained. “Alice In Wonderland is blatant. Eat me! She gets literally high, too big for the room.” Slick later told the Wall Street Journal that the song wasn't strictly about drugs: "It's about following your curiosity." Still, she admitted some regret about Jefferson Airplane's role in popularizing psychedelics. "LSD was new then. It opened up our heads and gave us new insight into the fact that reality isn't just one thing. That excited us. But it's also terrifying if your head isn't in the right place. So in hindsight, our advocating for LSD was kind of dangerous." (Wilkening)


1. The Beatles, "Lucy in the Sky With Diamonds"
From: Sgt. Pepper's Lonely Hearts Club Band (1967)

John Lennon had repeatedly denied that "Lucy in the Sky With Diamonds" has anything to do with LSD, even though most of the words in the song's title spell it out right there. The song was supposedly inspired by a painting of a classmate done by his young son Julian Lennon. Either way, it's the trippiest track found on Sgt. Pepper's Lonely Hearts Club Band, an album that arrived at the start of the Summer of Love and a cornerstone record of acid-popping hippies. Lennon waved away the fanciful imagery ("tangerine trees and marmalade skies") as an influence of Alice in Wonderland, an obsession at the time. Maybe he was telling the truth, but that hasn't stopped fans from bending it elsewhere. (Gallucci)

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