Flow is one of Finland's main summer festivals. Performing acts are chosen in accordance with current trends. There is local and international indie pop, hip hop, and electronica, as well as several alternative or mainstream music giants as headliners. Past guests of the festival include Kanye West and Björk. Like many major festivals, Flow strives to be environmentally responsible. It works towards waste minimization and encourages people to come by bike. To attend the festival you must be 18 or older.