The route follows the M-611 from start to finish. It sets off from Soto del Real, passes through Miraflores de la Sierra and from there the real climb begins, up to the Puerto de la Morcuera. On the other side the road drops towards the Lozoya valley and ends in Rascafría. It is a direct way to cross the Sierra de Guadarrama without going over Navacerrada.
It crosses the municipalities of Soto del Real, Miraflores de la Sierra and Rascafría, around the Parque Nacional de la Sierra de Guadarrama. The climb from Miraflores is the twistiest part, through pine forest with views towards La Pedriza and the plain; at the top the landscape opens out into mountain meadows, and the descent to the Lozoya is more open, with the valley and Rascafría ahead. The Monasterio de El Paular lies near the end.
It is about 34 km and almost an hour without stops, with more than 100 bends and four hairpins. Altitude ranges from about 920 m to 1,776 m, so the weather can be very different at the foot of the pass and at the top. There are many cyclists, especially at weekends, and livestock may be on the road in the upper section: leave yourself room on blind bends.