When you have a hobby, passion, and a whole lot of time on your hands, anything is possible. Just ask these Swedish surfers, who decided one day that they didn’t want to drive to the beach, and built a wave in a local mill stream.

Using just a wooden ramp shaped like a skateboard quarter-pipe and some sturdy tow cords, YouTuber dankandankan, his brother, and a friend created a standing wave in a shallow, fast-flowing mill stream and used a custom surf board to shred their miniature slice of the ocean.

Like a treadmill, but way gnarlier, bro. 

River surfing is popular across the world, even in places with righteous ocean waves in their own right, like Hawaii. But the mechanics of a standing wave are different than an ocean wave. Standing waves are stationary, caused by a large buildup of water as a fast-moving waterway flows over a rock, or in the Swedish guys’ case, a ramp. The surfer faces upstream and gets the same feeling of speed, without actually moving anywhere. A bunch of guys with some wood and a mill stream essentially created the same kind of artificial surf pool you find at resorts and on cruise ships.

The Swedish dudes look like they're having way more fun.

Similarly, river surfers often ride tidal bores, which are created when the incoming tide backs up against an outflowing river and creates a wave moving upstream.

Check out this legendary video from 2008, where a bunch of surfers in Oahu, Hawaii, dug a channel through the beach to connect a large stream to the ocean tide, creating a couple of monster hybrid standing wave tidal bores.

But not every landlocked surfer is satisfied with standing waves. For years, professional surfers and engineers have tried to create a natural wave artificially. But it’s difficult to get thousands of gallons of water to move exactly how they have to in order to get tubular. However, in late 2015, surfing legend Kelly Slater announced that he’d done it. Slater hasn’t released much information, and he’s still keeping his barrel-making facility top-secret, but you can watch the video here and make up your own mind.

But that stuff is the big time — for now, as promised, just watch a bunch of happy Swedish guys mess around in a mill stream. There are lots of high-fives.