Detour #217: Durango Unchained, Highway 40D, Mexico
With 115 bridges and 61 tunnels Highway 40D is Mexico’s civil engineering masterpiece.
Just a decade ago the only way to get from Durango to Mazatlán on Mexico’s Pacific coast was to brave one of the most treacherous roads in South America. El Elspinazo del Diablo – The Devil’s Backbone – with its sequences of switchbacks through the mountains of the Sierre Madre, not only saw hundreds of accidents, but it could take up to eight hours to make the journey.
In 2013 the Mexican government created a new link between the two cities which quadrupled the capacity to move people between them. Highway 40D unlocked travel for an estimated five million vehicles every year and halved the travelling time.
But don’t get the idea that this is a dull drive. To pass through the mountainous terrain engineers had to build no less than 115 bridges and 61 tunnels. They blasted through the rock with passages as long as 1.7 miles, and constructed extraordinary roadways high above the canyons.
The literal highlight is the Puente Baluarte which sits 403m (3,687 feet) above the valley below and has a span of 1,124 metres. The record-breaking bridge is the highest in all the Americas, the third highest in the world, and the highest cable-stayed bridge on the planet. It’s around the mid-point of the journey and is shortly followed by the longest Túnel el Sinaloense. From here the road twists and turns as it descends towards the Pacific Ocean and its termination at Mazatlán.
Despite the phenomenal engineering and expense Highway 40D has been plagued with problems from potholes to collapsing tunnels. Even today it is still prone to closures from rockfalls, while snow at its highest point at 2,745m (9,000ft) can also shut it down.