The pass of Piedrasluengas, at 1.355 m, is a mountain pass between the province of Palencia and Cantabria (Spain), which crosses the Cantabrian mountain range, linking the Palencian town of Cervera de Pisuerga with the Cantabrian town of Potes, in the Liébana region.

The pass reaches a maximum altitude of 1,390 m above sea level, via the road known as CL-627 for Castile and León and CA-184 for Cantabria.

In any case, the toponym comes from the nearby Palencia hamlet of the same name (Piedrasluengas [es]); and indeed, next to it, some large stones that form curious shapes are very striking.

[2][3] Its route gives rise to two ancient routes such as the old Roman road that evolved into the Royal Way of La Valdavia and the Roman road of Burejo, which also left from Pisoraca [es] and crossed the Cantabrian mountain range through this pass.

[4] The valley formed by the river Bullón [es] serves as a natural pass through the mountains, and a large part of the route runs parallel to it.