The bypass highway stands to the south of the urban nucleus of Huesca, and runs between the A-23 highway and the A-22 highway. During the preliminary design phase a multi-criterion analysis was made of two environmentally compatible corridors (North and South) and 4 alternatives (North, centre, South-centre and south). The option selected was the Southern alternative, 20.6 km in length, with up to 27 m of levelling work, 4 junctions and a design speed of 120 km/h. This was followed by the route and detailed design phase. Key structures included 47 cross-drainage culverts, 5 viaducts of up to 133 m, 12 overpasses, 15 underpasses, a 33 m bridge over the river Isuela and another 65 m bridge over the River Flumen.