Recently, I came back from a 10-day journey down the Amazon River. Never before in my life have I witnessed water so forceful, undeniably powerful, and beautiful. To put the strength of this river into perspective, in one second the volume of water dissipated from the rivermouth into the Atlantic Ocean could supply water for the entirety of New York City for two years!

As a surfer, one thing I was particularly interested in learning about was the Pororoca, a tidal bore phenomenon that occurs in late February / early March. Tidal bores are created when the leading edge of an ocean tide meets a river. In the case of the Amazon, the tidal bore forms one of the longest — if not the longest — surfable features on Earth, sending waves miles upstream, with wave heights of up to 18 feet.

“The wave feels much more like a river wave than an ocean wave, but you’re physically moving like in the ocean, and you’re watching the shore go by. It really was a mix of ocean and river wave surfing,” explained Olympian kayaker Corran Addison in an interview with kayaksurf.net.

Since 1999, an annual championship has been held in São Domingos do Capim. In 2004, 43-year-old Brazilian surfer Picuruta Salazar rode the wave in Amapa in northeastern Brazil for 7.5 miles, setting an epic record of 37 minutes.

Forget warm, clear water and easy swell — riding the Pororoca includes dodging debris, unpredictable conditions, and predatory wildlife.