Lagoa das Furnas is a Portuguese lagoon, located on the Azorean island of São Miguel, Azores archipelago, in the locality of Furnas, municipality of Vila da Povoação and is related to the volcanic formation of Furnas. It is located at an altitude of around 600 meters.
It is surrounded by abundant Macaronesian vegetation, as well as abundant volcanic manifestations such as Fumarole, sulfatara and boiling water boilers. On the banks of this lake and due to the boiling volcanic waters, traditional Cozidos à Portuguesa are made, underground with the heat of these volcanic manifestations.