Casa Colombo is a small museum in Vila Baleira, housed in a stone building traditionally associated with Christopher Columbus's time on Porto Santo. The displays cover the island, Portuguese navigation, maps, portraits, and the Columbus connection without pretending that this quiet town was the centre of the world.
It is a short visit, but a worthwhile one. The museum gives cultural weight to an island that many people otherwise treat as a beach with a ferry timetable, and it sits close enough to the centre that you can fold it into a slow wander through Vila Baleira.