The San Marcos Viaduct is in Mexico, in the Nuevo Necaxa - Ávila Camacho section, belonging to the Mexico D.F.-Tuxpán corridor, which will improve communication between the federal capital and the Gulf of Mexico coast.
This 36-kilometre long section, constructed by FCC Mexico in a joint venture with the Mexican company ICA, crosses the Sierra Madre Oriental in a region of difficult terrain that required the construction of six tunnels and twelve viaducts with a total length of six kilometres.
Pier 4 is 208 metres high and places this viaduct as the second highest in the world behind Millau in France.
The San Marcos Viaduct is 850 metres long and has 180-metre spans, with an 18.7-metre wide single deck for both motorway roadways.
Pier 4 was constructed using auto-climbing formwork: its construction used highly-advanced climbing and pumping equipment, which allowed high-performance execution without any incidents despite access difficulties.