Honna Surf Hub (formerly branded CityWave) sits inside the X Madrid shopping center in Alcorcón, on the edge of the city, and it's become the go-to indoor wave for Madrid surfers who don't want to drive to the coast. The pool runs a continuous artificial wave with instructors on hand for everyone from first-session beginners to surfers chasing more advanced moves. Sessions run about an hour and aren't cheap—figure €40 to €50 a pop—but that gets you full gear rental, a surf shop, and a cafe looking right out over the wave. It's commercial and polished, but it's real, repeatable surf minutes from downtown Madrid.