Whidbey Island is the 4th largest island in the continental United States and forms the northern boundary of Puget Sound. 

The Whidbey Island Traverse begins at the island's northern terminus (Hoypus Point) and continues south 54 miles to the southern terminus (Possession Point). 

There are a number of trails and roads facilitating north-south passage on Whidbey, though West 20 and South 526 are the most direct before taking Bayview, Sills, and Possession roads to reach the southernmost point.