Colours of Ostrava is the Czech Republic's biggest multi-genre music festival, held over four days in mid-July at the Lower Vítkovice industrial site. Past headliners have included Björk, the Black Keys, Massive Attack, Florence + the Machine, Kraftwerk and the Cure — the curation is genuinely broad, mixing world music, electronic, indie and global pop on a dozen stages.
The setting is the draw: stages set up between blast furnaces, after-parties in the gas holders, the Bolt Tower lit up overhead. Tickets sell out months in advance; check the festival website in spring.