Navacerrada mountain pass Nature · Navacerrada, Cuenca del Guadarrama, Madrid The Puerto de Navacerrada is a pass at 1,858 metres in the sierra de Guadarrama that separates the provinces of Madrid and Segovia; its northern slope belongs to the Segovian municipality of Real Sitio de San Ildefonso and its southern slope to Cercedilla, in Madrid. It is the natural passage between the peaks of Siete Picos and the Bola del Mundo, and through it runs the boundary between the Siete Picos and Peñalara massifs. The current route, designed in 1778 by the royal architect Juan de Villanueva to replace the old road over the Puerto de la Fuenfría, was not opened to traffic until ten years later, under Charles IV, and was a regular route for kings and ministers on their way to La Granja de San Ildefonso. It held a ski resort in operation from the late 1940s until its final closure on 25 March 2025. Photo: Rodelar (CC BY-SA 4.0) What to see and do in Navacerrada