LAS VEGAS (AP) — Adele, Mariah Carey and Garth Brooks tower over the Las Vegas Strip, peering out from billboards advertising their various casino residencies. But the 20,000 fans marching toward the glowing Sphere last week were there for a band that many Strip visitors have no idea exists.

Over the past 40 years, legions of dedicated Phish fans have followed the Vermont jam band no matter where it goes. This time, it happened to be Las Vegas, for four nights at the $2.3 billion immersive arena. No two Phish shows are the same, and while the band had played Vegas 26 times before, the Sphere offered a game-changing canvas for its signature light shows.

The fans came in sequined, glittery dresses and tie-dye alike, in button-down shirts and overalls printed with the band’s red doughnut logo. Once inside, they were greeted with a LED screen the size of a football field.