Surfing is an ocean sport. The most surfable waves in the world break over reefs, sand bars or shallow areas near the shoreline. Rivers can also provide surfing excitement, too, far away from these powerful ocean swells. Admittedly, surf-worthy river waves are few and far between, but when they do occur, they often offer consistent conditions and the kind of never-ending rides that ocean surfers can only dream about.
River waves come in two varieties. The first are tidal bores, and they occur when ocean tides are funneled into slow-flowing rivers. The result of this rare phenomenon is a wave that surfers can ride upstream for miles and miles. There are approximately 60 tidal bores in the world.
The other type of freshwater surf wave, the standing wave, occurs when a high volume of water rushes over a rock or shallow area in a rapidly-moving river, such as in Munich's Eisbach (pictured). This results in a stationary "wave" that surfers can ride continuously by pointing their boards upstream.
Because of the ability to ride for long periods of time and the relative predictability of river waves compared with ocean waves, the sport of river surfing is growing in popularity. Here are nine destinations that have earned buzz from the surfing community.