Maritime Museum of Cantabria is a maritime museum that adds a useful stop to the Santander things-to-do map. Santander museum covering Cantabrian seafaring, marine biology, and the Bay of Biscay. It is worth listing for travellers because it gives the destination a more specific texture than another general viewpoint or shopping street.
Plan it as a focused visit rather than a whole-day anchor unless you already know this is your special interest. Check the official site before going for current opening hours, tickets, and seasonal closures, then pair it with nearby sights in Santander so the detour makes sense on foot, by transit, or by taxi.