
Surfing the Silver Dragon —
Each year, international surfers compete on Qiantang River, riding the "Silver Dragon" wave, which flows through the city of Hangzhou.

Surfing the Silver Dragon —
Each autumn, the nine-meter tall tidal bore -- a continuous wave which travels against the current -- surges along the river.

Riding high —
The Qiantang River is just one of a growing number of inner-city surfing spots around the world. Munich's Eisbach River (pictured) has been a popular surfing destination for more than four decades.

Water works —
The German river is nestled in the heart of Munich's English Gardens, attracting surfers late into the night and a steady stream of onlookers.

Urban pusuit —
Here, surfer Alex Foerderer waits for a train to Eisbach. It was illegal to surf the icy brook until 2010, when the city of Munich allowed experienced surfers to ride the one-meter waves.

Swiss sports —
Land-locked Switzerland might also seem like an unlikely surfing destination. But popular snowboarding spots have provided an ideal training ground for the next generation of surfers.

Watch and wait —
Many villages in Switzerland overlook a river, with thrill-seekers now lining up to take the plunge in gushing brooks across the country.