Turnagain Arm is the long, narrow fjord that the Seward Highway follows south of Anchorage, and this stretch is among the most dramatic coastal riding in the north. The road clings to the edge, with the Chugach Mountains plunging down on one side and the grey-brown water on the other, and on a clear day the far shore of the arm shows snowy peaks.
The tide is the thing to understand. Turnagain Arm has one of the biggest tidal ranges in North America, with a difference of up to about nine metres, and the incoming tide forms a bore, a low wave that races up the arm. The mudflats are treacherous, soft glacial silt that can trap a person, and every few years someone has to be rescued. Pull-offs along the highway give you safe viewing, and on a good day you may spot beluga whales hunting salmon at the turn of the tide, as well as Dall sheep on the cliffs above the road.
The name itself comes from Captain Cook's search in 1778 for a passage to the Atlantic. He explored the arm and found it a dead end, and had to turn again, hence Turnagain. The Dena'ina people lived on these shores long before, fishing and hunting, and Russian and American traders followed.
The ride is lovely, wide and well-surfaced, with passing lanes and viewpoints, though it can be busy on summer weekends with campers and tour traffic. The corners are broad and the views frequent, so the main challenge is concentrating on the road. Wind can blow hard along the water, especially when the weather changes. Bring a warm layer, because the breeze off the glacial inlet is cold even in July. If you see wildlife, pull off completely before stopping, and don't leave the bike where it blocks the viewpoint entrance.