Bristol Channel, inlet of the Atlantic Ocean, c.85 mi (140 km) long and from 5 to 50 mi (8.1-80 km) wide, stretching westward from the mouth of the River Severn and separating Wales from SW England. Its chief bays are Carmarthen and Swansea in Wales and Barnstaple (or Bideford) and Bridgwater in England. Many cities are on or near the channel; among the largest are Bristol, Newport, Cardiff, and Swansea. Along the coast of S Wales is a great concentration of economic activity, and Bristol Channel serves as a major shipping corridor. Milford Haven, a major oil-importing center, has a harbor that can accommodate large modern tankers.

Inlet of the Atlantic Ocean, southwestern England. It extends about 85 mi (135 km) between southern Wales and southwestern England, ranging from 5 to 43 mi (8–69 km) wide. Lundy Island, once a pirate stronghold, lies in the centre of the channel; it is maintained as a trust preserve. Ships using the English port of Bristol and the Welsh ports of Swansea and Cardiff pass through the channel.

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