See map of viaduct Additional photos of the infrastructure The company, a subsidiary of Ferrovial, is in the final stages of building the Molledo-Pesquera stretch of the A-67, which measures 11.87 kilometres. The project was awarded by the Infrastructure Ministry, which owns the road. The highway, which will replace the N-611, will incorporate various unique structures with a view to traversing the area's complicated relief. To date 1.6 kilometres of tunnels and one cut-and-cover tunnel have been built, as well as five viaducts measuring 1.9 kilometres in total. There are also three overpasses and four underpasses. The most noteworthy viaduct, at Montabliz, will be one of the largest structures of its kind in Spain once it is ope rational. Measuring 721 metres in length, it crosses the deep valley of the Bisueña River using an environmentally-friendly solution. The viaduct has a single, five-lane deck supported by four piers to minimise the bridge's footprint and visual impact. The bridge has five spans measuring 110, 155, 175, 155 and 126 metres. At its highest point, the viaduct is 150 metres above the valley floor, and the tallest pier is 140 metres high, i.e. the tallest in Spain and one of the tallest in Europe. Only a few viaducts, such as Millau in France and Europabrücke in Austria, are taller than Montabliz. The construction of the viaduct posed a challenge for Ferrovial Agromán, which used innovative techniques in its development. For example, the formwork of the piers was completed using a novel self-climbing system. The lateral cantilevers were built with prefabricated slabs on ribs that were built on site. The deck totals 18,818 square metres. Ferrovial Agromán is specialised in complex projects such as the Arco de Tilos on the island of La Palma, the Guggenheim Museum in Bilbao, Barajas Airport's new Terminal 4 and the tunnelling work for Madrid's M-30. Ferrovial's Construction division recorded 3.783 billion euro in revenues between January and September. At the end of September, the company's backlog amounted to 8.803 billion euro, a 13.3% increase on the previous year.