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Photo: diverus from U.S. A., CC BY 2.0 via Wikimedia Commons
This section of ocean water near Girdwood is home to the second largest tides in North America and one of the few bore tides in the world, an occurrence where due to the length of the arm and the height of the tides the come in as a wave.
Turnagain Arm is a waterway into the northwestern part of the Gulf of Alaska. It is one of two narrow branches at the north end of Cook Inlet, the other being Knik Arm. Turnagain is subject to climate extremes and large tide ranges.
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