This museum, in a modern two-storey building, opened to the public in 1981, although its origins date back to 1886. Inside, all aspects of marine life are represented, from tanks of sting rays, sharks and turtles to displays explaining the daily life of Santander's fishermen. Other sections are devoted to ship building, the different types of boats used locally, marine cartography, navigation systems and water sports. The museum also programs temporary exhibitions and runs its own research projects. These vary from investigations in marine biology to the techniques and practice of sub aquatic archeology. The sea has always played an important role in Santander's history, and this museum is a fascinating place to visit and find out more. Admission is free.