Lozoya-Chorrera de San Mamés 20.06.15

Clockwise route with the Club, 33.5 km in 2:57 and a total of 3:41 hours. Moderate difficulty due to 10 km of constant climbing up to La Horizontal, the descent via the firebreak, and the climb at km 26.6 after Navarredonda. So, an ascent up to km 10 with a chain break incident, then nearly 3 km along La Horizontal before diverting via the firebreak, practically all downhill afterwards, picking up another trail lower down leading to the Chorrera de San Mamés, which we didn't approach due to time constraints. That would have added half an hour and sections on foot. We didn't reach San Mamés because we diverted towards the dehesas between San Mamés and Navarredonda, where I suffered a puncture caused by a piece of barbed wire on the ground while trying to open one of the gates. Since the tires were tubeless, after losing pressure, we managed to seal it with Loctite and reinflate. After crossing Navarredonda, at km 26.6 the slope steepens for about 400 m. From this height, it’s downhill towards Lozoya. A nice route that deserves further exploration to try to extend it a bit more along La Horizontal and to finally get to the Chorrera. Note: The GPS track shows unusual readings on some 180° turns.