Davis Strait, a sea passage connecting the Atlantic Ocean to Baffin Bay and separating southern Greenland from Canada's Baffin Island. It is roughly 400 miles (640 km) long and, at its narrowest point, 200 miles (320 km) wide. The strait is ice-free for only a few months each year. It was discovered by and named after the English navigator John Davis, who explored its shores in search of the Northwest Passage in 1587.