Burning Man, a festival-esque gathering that has taken place annually since 1986, has experienced a grave loss this weekend.

As confirmed by Burning Man Project CEO Marian Goodell, the influential gathering’s co-founder and “chief philosophy officer,” Larry Harvey, has passed away. He was 70.

For those who may be unfamiliar, Burning Man is held annually the week before Labor Day and reportedly attracts roughly 70,000 attendees each year. During the festival, which is held in Northern Nevada’s Black Rock Desert, a massive wooden figure is burned to the ground in celebration, thus how it got its name.

According to reports, Harvey died Saturday (April 28) while surrounded by family in San Francisco. The cause of death was not immediately known but he had suffered a stroke earlier this month.

In the wake of the news, past attendees of the gathering penned heartfelt messages on Instagram, thanking Harvey for sharing his vision with the masses and for creating a true artist community. See the statement honoring Larry Harvey’s legacy, below.