The funny thing about indoor cycling is you pedal for an hour, but you don’t actually go anywhere. OK, if you go to SoulCycle, you might be spiritually transported, but you’re still in the same room.

What if your indoor cycling class could take you somewhere? Hop aboard the Paris Navigating Gym. The 45-seat boat travels down the Seine powered by all that pedaling, so it’s super green too. Carlo Ratti Associati, the firm that designed the floating gym, says it could be ready for riders in 18 months. Now you have another excuse to visit Paris.