The museum, just like its name says, is next to the ria of Bilbao.
I went there when I was in high school, during a field trip to get to know the most important places in Bilbao. The interior part is divided into three main themes: 1. The ria, sea port; 2. The ria; 3. The ria, naval shipyard.
The three areas have monographic blocks evoking the hulls of a vessel. This is the best way to know the ria of Bilbao and its characteristics.
In the exterior part you will find the ancient dikes of the shipyard Euskalduna, where the boats find shelter aside the Casa de Bombas and the Grúa Carola (a crane).