bassmania xxl is a large indoor multi-genre festival that has run for over twelve years, billing itself as the biggest indoor festival in the north rhine-westphalia region. it takes place across four separate clubs on a single site, described as the rawgelände of its host city, allowing attendees to move between venues within minutes.

across more than eleven floors, the programming spans hardtechno, psytrance, gabber, tekke, trance, techno, bouncy house, and raw, alongside outdoor areas, chillout spaces, and bars. the multi-club format means the event runs regardless of weather.