Woodstock co-creator and organizer Michael Lang has died at 77, as Variety reports. He passed away on Saturday at Sloan Kettering in New York City — his cause of death was a rare form of Non-Hodgkin’s lymphoma.

Lang was born in Brooklyn in 1944. He got his start promoting concerts in the Miami area, eventually co-producing the 1968 Miami Pop Festival that featured a lineup that included Jimi Hendrix, Frank Zappa, and John Lee Hooker. After moving to Woodstock, NY, he linked up with fellow co-founders Artie Kornfeld, John P. Roberts, and Joel Rosenman to put on the legendary Woodstock Music And Art Fair in 1969 on a farm in Bethel, NY.

Lang went on to start his own production and management company, and he mounted two Woodstock follow-ups in 1994 and 1999 — the latter was recently the subject of an HBO documentary. For the 50th anniversary of Woodstock in 2019, Lang tried to put on another Woodstock festival, but it was eventually cancelled.