Route to the Purgatorio waterfall Activity · Rascafría, Sierra Norte, Madrid A classic walk in the upper Lozoya that sets off from the surroundings of the monastery of El Paular and covers some 6.5 kilometres through pine woods to the waterfall that the Aguilón stream forms over the granite boulder fields of the Guadarrama massif. Photo: MsLids (CC BY-SA 3.0 es) What to see and do in Rascafría