Porto Moniz is most famous for its natural swimming pools sheltered by lava formations. Some have been turned into a commercial bathing complex with a sun deck, showers, lockers, etc., while others remain free to use: your feet may need some protection from sharp rocks.
As a convenient stopping point for touring the north-west coast, Porto Moniz offers parking, restaurants and accommodation.
Although car access to Porto Moniz has been much improved by the network of road tunnels, the Rodoeste bus 80 from Funchal takes over 3 hours during the week and rather less at the weekends (when it stops are more limited) as it serves settlements along the route: there is one service per day in each direction. It's a stop on many organised bus tours and on some walking tours, for example to the Levada dos Cedros.