Ribeiro Frio, Madeira
Not far from Santo da Serra, on the northern slopes of the island, is Ribeiro Frio (meaning 'cold river') which is popular with tourists for its scenery, the trout farm, and is the starting point for a popular levada walk.
Ribeiro Frio’s governmental trout farm is well worth a visit. You can view the hatchery where there are trout of all ages separated by their own tanks. If you are a real "trout fan" there is even a local restaurant for a trout lunch!
Tip from Mark Blezard: Driving around the island can prove stressful if you are anything less than a competent driver (especially if you are used to RHD vehicles). I'm not saying don't do it, just plan your journey in advance and perhaps consider the taxi day tours.