Let KAYAK do the searching
Based on KAYAK hotel searches, the most popular destination is San Sebastian (51% of total searches to Bay of Biscay). The next most popular destinations are Bilbao (29%) and Biarritz (12%). Searches for hotels in La Rochelle (8%) are also popular.
KAYAK users have found double rooms in Bay of Biscay for as cheap as $36 (Oviedo) in the last 3 days. The average price is $413.