A swimming pool on water, there’s something you don’t see every day.

Called the Badeschiff (that’s German for “bathing ship”) this floating swimming pool is really just an old barge transformed into a public pool last year in Berlin, on the Spree river. Unfortunately, the river itself is much too polluted for people to swim in, so this idea, as crazy as it looks, makes some sense.

It was first spotted in 2007, during a very hot Summer and during the off-season it’s covered and closed to the public. But the hot Summer is here again and the Germans in Berlin will once again be able to enjoy a swim in the cool water of the Badeschiff. Would’ve been cool if it had a glass bottom though, so you could see the river.