Alto de la Marta
Alto de la Marta is a mountain pass at an elevation of 1.105m (3,625ft) above the sea level, located in northwestern Asturias, Spain. The steep road includes 15% and 18% sections.
The road over the pass is asphalted. It’s called AS364 and is very steep and narrow. The road includes some steep sections, without market central lines, is very narrow, scarcely wide enough for two cars to pass at the same time and there are no protections or guard rails along some parts of the route. It is a long climb with a meagre average gradient, but this doesn't stop it from being a real killer, with several steeper sections.
This road is usually open all year, but it can be closed anytime when the access is not cleared of snow. There are 2 routes to reach the summit. Starting from Puente Polea, the ascent is 27 km long. Over this distance, the elevation gain is 952 meters. The average percentage is 3.5 %. And starting from Pola de Allande, the ascent is 10 km long. Over this distance, the elevation gain is 556 meters. The average percentage is 5.6 %.