Collada de Montaner

Collada de Montaner is an international high mountain pass at an elevation of 2.079m (6,820ft) above the sea level, located on the Spain-Andorra border. 

Collada de Montaner

The road to the summit, located within the Pyrenees mountain range, is gravel, rocky, tippy and bumpy at times. The road is usually impassable from October to June. Great trail for experienced wheelers. Avoid driving in this area if unpaved mountain roads aren't your strong point. 4x4 required. Stay away if you're scared of heights. Expect a trail pretty steep. Wet conditions may make for tough driving along the muddy road. 
Pic: https://es.wikiloc.com/rutas-mountain-bike/andorra-la-vella-pal-andorra-la-vella-per-collada-de-montaner-394778/photo-103943