The Ribeira dos Caldeirões Natural Park is an Azorean protected area, located on the slopes of Serra da Tronqueira and which occupies part of the course of Ribeira do Guilherme. Here, one can observe an abundant and varied Macaronesian flora, where Laurissilva is dominant. There are also abundant masses of hydrangeas and large cryptomeria. It is noteworthy the existence of a beautiful waterfall that feeds part of the park and mills dating from the 16th century, some still functioning and one of them running an ethnographic museum.