Bicycle Day is the annual celebration of Swiss scientist Albert Hoffman’s first intentional ingestion of the chemical compound, LSD-25, after accidentally discovering the compound’s psychedelic nature three days earlier. Named for Hoffman’s trippy bicycle ride home from the lab that fateful day, each year on April 19th, folks come together to celebrate the world’s first acid trip back in 1943. This year, Bicycle Day will be celebrating its 75th anniversary, and the folks at Euphonic Conceptions and Legion of Bloom Music have something really special cooked up to celebrate the landmark year.

Last year, the promoters continued their annual San Francisco tradition, bringing musicians, visual artists, and speakers together to pay tribute to America’s counterculture and all things psychedelic at the home city of one of the largest Bicycle Day celebrations in the world. This year, in honor of the day’s 75th anniversary, Euphonic Conceptions and Legion of Bloom Music will take their celebration on the world, hosting three parties over three days in three cities across the United States. Thus far, renowned visionary artists Alex Grey and Allyson Grey have signed on to return for the event in addition to internationally acclaimed producer Shpongle (Simon Posford live) and CharlestheFirst.

On Bicycle Day proper, April 19th, the event will return to its home at The Midway in San Francisco, the larger venue that the event moved to last year. The following day, on April 20th—which has become a holiday for users of a different (sometimes) illegal substance—the party will move south and take over The Mayan in Los Angeles. Rounding out the weekend, the Bicycle Day tour will hit New Orleans for a performance at the Joy Theater on April 21st.

Tickets for the various stops on the Bicycle Day 75th Anniversary tour are currently on sale. For the 4/19 San Francisco show, head here. For the 4/20 Los Angeles show, click here. For the 4/21 New Orleans show, head here.

Watch the 2017 recap video of Bicycle Day below!