Channel in the Pacific Ocean, southwestern Canada and northwestern U.S. Located between Vancouver Island , the southwestern mainland of British Columbia, and northwestern Washington state, it is 150 mi (241 km) long and 30 mi (28 km) at its widest.
To the north the strait ends in a jumble of islands separating it from Johnstone and Queen Charlotte straits. The southern end is marked by the San Juan Islands of Washington and joins Haro Strait, forming a link in the Inside Passage sea route between Seattle , Wash., and Skagway, Alaska.