Turnagain Arm and Knik Arm are branches of Cook Inlet south of Anchorage. Back in 1778 Captain Cook sailed first up the Knik Arm only to discover that it was the mouth of a river and not an opening to the Northwest Passage, then sailed up the Turnagain Arm only to find out that it, too, was not the opening to the Northwest Passage and they had to turn again.
We drove the car about 20 miles south along the Seward Highway along side Turnagain Arm. It’s a very beautiful and scenic drive with very heavy traffic. Our first stop was at Bird Creek, a popular salmon fishing spot. There were about 20 people fishing when we were there. A large number of Grizzly bear like to fish here too. Signs tell you to take your fish to your car and not to clean them in the water. Always yield to the bear.

Fishing at Bird Creek
Construction of the Alaska Railroad led to the unintentional creation of Anchorage’s most popular wildlife haven. Potter Marsh has a nice long boardwalk with interpretive signs and viewers. A few ducks and a few salmon were the only wildlife we saw.

Potters Marsh Boardwalk
Speaking of being in the right place at the right time…. I never heard of a Bore Tide before. Turnagain Arm’s tidal bore is a breaking wave that rushes in and can be from 6 inches to 6 feet in height and could reach 10 feet high.
Wikipedia explains this as a rush of seawater that returns to a shallow and narrowing inlet from a broad bay. Bore tides come in after extreme minus low tides created by the full or new moon. It takes not only a low tide but also about a 27-foot tidal differential (between high and low tide) for a bore to form in Turnagain Arm. It’s like the high tide starts rolling in before the low tide waters are finished rolling out and they crash into each other. Your chances for seeing a large bore are best during the five-day window that surrounds the new and full moons.
And today is day 5 of that window and we arrived at the best viewpoint just at the right time to see it. A crowd of people was gathering for the event.

Tidal Bore at Turnagain Arm, Anchorage, Alaska
OK, so it wasn’t tremendous but it was cool to be able to witness such a geological rarity. There are only about 60 of these that occur all over the world, and the one at Turnagain Arm is the biggest one in the world and the only one that occurs in the far north and the only one bordered by mountains making it the most unique and the most geologically dramatic bore tide in the world.
On our way home we stopped at Ship Creek in downtown Anchorage. There were several people fishing here too. That building behind the fisher people is the Bridge restaurant, a popular seafood restaurant.

Ship Creek Fishing