Surfers in Alaska ride waves for an astonishing five miles

For most surfers, a really long ride might last about 20 seconds and cover 50-60 yards, so imagine the thrill experienced by a group of standup paddlers recently when they rode waves for a distance of nearly five miles -- amid the splendor of the pristine Alaskan wilderness.
The magical event played out on the Turnagain Arm in the Cook Inlet near Girdwood, thanks to a phenomenon called a tidal bore, caused when the leading edge of an incoming tide pushes against an opposing current or the direction of a river. This creates actual tidal waves.

Tidal bores occur in very few places around the world and the Turnagain Arm exhibits a tidal bore only when conditions are right.

Surfers often try to predict when this will happen. They can ride the waves but with traditional surfboards it's difficult to stay on them for the duration, because they can suddenly diminish before building again.

However, the advent of larger standup boards, on which surfers use a paddle for propulsion, has maximized the Turnagain bore experience.