Bristol Channel is an arm of the Atlantic Ocean between south Wales and the western peninsula of England. It is from 5 to 43 miles wide and about 90 miles long, terminating in the estuary of the River Severn.
The largest inlet of England, channel has an irregular coastline of 220 miles. In addition to the Severn, the channel receives the rivers Towy, Taff, Usk, Wye, Avon, Taw, Torridge, and some others. Of the bays along the channel, Barnstaple, Carmathen, Milford Haven, and Swansea are the largest. The channel is noted for its high tides, which at Chepstow rise 47 feet in the spring. Situated along its shores are Bristol, Swansea, Gloucester, and Cardiff.