The Bay of Biscay was the name given to the gulf which extended from the west coast of France to the north coast of Spain. (TV: War of the Sontarans) It was next to the Atlantic Ocean. (PROSE: History 101)
The city of Bilbao was on the coast of Spain, just south of the bay. (PROSE: History 101)
The Bay of Biscay appeared on General Logan's map of the eastern hemisphere in an alternate 1855. (TV: War of the Sontarans)