These works consisted in the completion of a section of road 6620 m in length, with one carriageway in each direction. From a structural viewpoint, it included the completion of: The Endarlatsa viaduct, a singular structure with a parabolic arch of more than 90 m of light. The Lamiarri, Lastaola, Alunda and Gurutze viaducts; Intxaurreta, Gurutze and Etxezar underpasses and the Intxaurreta and Lamiarri false tunnels. Two105 m and 500 m length tunnels known as the Intxaurreta and Lamiarri tunnel. These works as a whole included completion of levelling for road building with 1,241,810 m² of excavation, completed using mechanical means and blasting.