The Guarga River is short, just a few dozen kilometers long. Even so, over the course of its brief journey from its source in one of the ravines of the Sierra del Galardón in Huesca, it takes the opportunity to collect as much water as it can from the mountain. Its task is to bring that water to the Gállego and from there, to the Ebro.

That way, it makes up one of the great drainage basins of the Iberian Peninsula.

This water network naturally supports the northeast part of the Iberian Peninsula and the Pyrenees; the Mudéjar highway connects the region with the mountain range’s two faces, linking Valencia with Aragon and, from there, with France. Along their opposite routes, the A-23 and the Guarga intersect at one of the three large viaducts that bring shape to the highway, a bridge that takes its name from the river.

The Guarga viaduct was built by Ferrovial as part of the Caldearenas-Lanave stretch of the Mudéjar highway. It crosses the river with a mixed structure measuring 350 meters in length, divided into four sections with 75- and 100-meter spans. The deck is supported by Y-shaped piles connected with a metallic V shape; that piece, in turn, acts as arms, giving the bridge a recognizable structure from a distance.

To lay the viaduct’s foundation, the Guarga’s course had to be changed temporarily, but today, it runs along the same path as always. The structure, like the river, is part of a rugged terrain, which starts to rise towards the Pyrenees. This is why the Mudéjar highway not only has tunnels and viaducts, but also four wildlife crossings to protect the movements of species that inhabit the mountain.