bassmania xxl is a long-running multi-genre indoor and outdoor club event held across four interconnected venues on the hawerkamp, a repurposed industrial site that functions as a club compound in its city. running since 2009, it has grown into one of the larger recurring indoor festival formats in the region, spreading across more than eleven floors that cover hardtechno, psytrance, progressive trance, gabber, tekno, drum and bass, techno, raw, and house.

the event runs on a recurring monthly or near-monthly schedule through the warmer part of the year, with each edition using the same multi-club setup and the same broad stylistic spread. the psytrance and progressive floors have been part of the programming for years, sitting alongside the harder techno and gabber rooms as one strand in a deliberately wide-ranging format.