The Black Circuit 4 is demanding has the grade color indicates with steep climbs and significant accumulated climb and downhill considering the total distance. It goes through the west slopes of Espinhal Mountain, including the abandoned village of Esquio, and through the Alge Stream valley, passing by Campelo, Silveira and Tarrasteira villages. It is recommended for keen and avid cyclist, well trained and looking for a hard but rewarding journey. Don't expect to find a lot of drinking water supply.