Critical Mass on the Wisła

A bit of a cross between critical mass and a kinetic sculpture derby, this relatively new tradition involves DIY dirigibles floating down the Wisła River through the heart of the city. Anyone can participate, but you'll need a boat or other floating vessel of some kind in order to do so (some limited kayaks are available if you get there early). Promoting a natural and clean Wisła, the goal is to have as many vessels in the water as possible, and participants are encouraged to create their own floating vessel - out of any materials (it just has to float!) - and a premium is put on pageantry, costumes and colour. Enjoy the parade of river selkies, mermaids and more from the shore, or better yet, get involved yourself. After the float trip there will be an afterparty (concerts and DJs).