Bay of Biscay
The Bay of Biscay lies between Brest, on the Brittany Peninsula, and the north coast of Spain. The northern half of the bay is quite shallow, overlying the continental shelf, but this steeply drops away to the Biscay Plain, which is a small, partially opened ocean basin. Ships crossing the bay experience heavy seas, as full-size Atlantic rollers are amplified by the sudden shallow depth. There is a weak counterclockwise surface current within the bay. The Charcot Seamounts, Azores–Biscay Rise, and Kings Trough mark an inactive crustal fracture where the sea floor was once splitting apart.