I was in Alaska a few years ago on transportation that was 200 miles inland following this damp looking river.
All of a sudden in 30 degree silt in body suits lying on surfboards I see a wave coming.
It was the tide coming in and those surfers can easily ride the wave for three hours before the whole thing stops.
Very rare to see I hear and looked like some movie scene out of Escape from Los Angeles.
Seven people were in those body suits riding tides like waves.
Wow, that would freak me out a bit.