Every four years, millions of sockeye salmon journey thousands of miles from the ocean back to their native spawning grounds in Canada's Fraser River. There, after eggs are laid, the parents die. Then the cycle begins anew as the next generation of salmon makes its way down the river and into the ocean. ➡ Subscribe: http://bit.ly/NatGeoSubscribe About National Geographic: National Geographic is the world's premium destination for science, exploration, and adventure. Through their world-class scientists, photographers, journalists, and filmmakers, Nat Geo gets you closer to the stories that matter and past the edge of what's possible.