Frobisher Bay, arm of the Atlantic Ocean, 150 mi (240 km) long and from 20 to 40 mi (32–64 km) wide, Nunavut Territory, Canada. Cutting deeply into SE Baffin Island, it has steep, deeply indented shores and numerous islets. On its southwest side the Grinnell and Southeast icecaps rise to c.3,000 ft (910 m), extending tongues into the bay. At its head is Iqaluit, the capital of Nunavut. The bay was explored (1576) by Sir Martin Frobisher; until 1860 it was believed to be a strait separating Baffin Island from another island.