San Glorio pass is a mountain pass at an elevation of 1.609m (5,278ft) above the sea level, located in the Picos de Europa, a mountain range of Northern Spain. The pass is traversed by the N-621 road.
The surface of the road is asphalted, and chains or snow tyres can be required throughout the year. The pass is located on the border between Cantabria and Castile and León. From the pass, there is also a paved dead end for 2 km up to the Collado de Llesba viewpoint. The asphalted road over the pass connects the city of León with Cantabria.
There are 2 routes to reach the summit. Starting from Portilla, the ascent is 9 km long. Over this distance, the elevation gain is 389 meters. The average percentage is 4.3 %. And starting from Potes, the ascent is 26.7 km long. Over this distance, the elevation gain is 1.278 meters. The average percentage is 4.8 %.