An event advertised as "three days of peace and music" kicked off on a farm in Bethel, New York, on this day in history, Aug. 15, 1969.
The Woodstock Music and Art Fair, which would come to be known simply as Woodstock, was a three-day music festival with a lineup of present and future legendary music acts.
Some of the big names among the 32 musical acts included Jimi Hendrix, Janis Joplin, the Grateful Dead, Jefferson Airplane, Joan Baez, Arlo Guthrie, Santana, The Who, Crosby, Stills, Nash & Young, Creedence Clearwater Revival, Joe Cocker, and Blood, Sweat & Tears.
Subtitled "An Aquarian Experience: 3 Days of Peace & Music," Woodstock was the idea of John Roberts, Joel Rosenman, Artie Kornfeld and Michael Lang, notes the History Channel's website.
It also almost didn't happen.
The original venue, Howard Mills Industrial Park in Wallkill, New York, backed out of hosting and the organizers had trouble finding a new spot for their festival, notes the same source.
Only a month before the festival was to begin, a dairy farmer named Max Yasgur offered part of his farm to host the concert.
"With the concert just a month away, the four frantic partners jumped at the opportunity and paid his asking price," said the History Channel.
The event ran into another issue when attendees began arriving prior to the official start of the festival.
Key security features — fencing, gates, ticket booths — were not ready, and likely would not be ready by the time the show began.
Lang decided to prioritize the concert and the well-being of the attendees over charging ticket prices, and made Woodstock free to enter.
The organizers expected 50,000 people to come to the festival.
Due to the free show, it was impossible to get a true head count of attendees, but an estimated 400,000 people are believed to have descended upon Yasgur's dairy farm, said the Musicians Hall of Fame and Museum website.
The chaotic nature of the festival did not end with the lack of ticket security.
A schedule was only loosely followed, and some musicians played "hours or days after they were expected to," said the Musicians Hall of Fame.
The scheduled opening band, Sweetwater, got stuck in traffic on the way to Woodstock. As a result, Richie Havens and his two acoustic backup musicians appeared first on stage, according to the Bethel Woods Center for the Arts.
Also, helicopters had to be used to fly in food and water to attendees, according to the Musicians Hall of Fame.
While the festival was scheduled to last three days and end on Sunday, Aug. 17, it actually continued until Monday.
Jimi Hendrix closed out Woodstock with a performance at 9 a.m. on Monday, Aug. 18.
Hendrix had a line in his contract that stated he could not be followed by any other performers, said the Musicians Hall of Fame.
He ended his set with "The Star-Spangled Banner."
Despite the crush of people, logistical headaches and overall disorganization, the crowd at Woodstock was (reasonably) well-behaved for an event of its size.
About 80 people were arrested for various drug charges, but those who were smoking marijuana were left alone.
Although there were three deaths of attendees — two were drug overdoses; and one man in a sleeping bag was accidentally run over by a tractor — there were no reported acts of violence during the festival.
Some attempts to recreate Woodstock have resulted in disaster.
Woodstock 99, the 30th-anniversary show in 1999, was held in Rome, New York.
Unlike the original Woodstock, Woodstock 99 was a "grim descent into sexual violence, looting and rioting," said music magazine Pitchfork.
Woodstock 50, which was scheduled for 2019, never actually happened after repeated permit denials saw artists and other financial backers pull out of the event.
Even so, in 2017, the site of the 1969 Woodstock festival was placed on the National Register of Historic Places — "a formal acknowledgment of the significance of the site’s heritage," said Bethel Woods.