 The road starts 9 km south of Burgos on the Autovía A-1.It heads south east through the Sierra de las Mamblas rising over the Mazariegos (1,060m) and pass Muela (1,374m).It continues through the mountains tom Soria passing over the Puerto Mojón Pardo (1,234m) with the Reserva Nacional de Urbión in the Sierra de Urbión to the north rising to 2,229m.