El Paso San Boldo is a mountain pass of the Italian Alps, located between the cities of Trichiana and Tovena, in the Veneto region, Italy. The pass has a height of 706 meters. The most difficult part of the climb is a small section of about 700 meters including 18 numbered horseshoes, 5 of the curves, installed in separate tunnels that rid the mountain, connected by bridges. As you can see in the image above, it is impressive. El Paso de San Boldo is one of the most scenic, mythical, impressive and touristic mountain passes in the world. The pass is part of the regional road SP 635.

Although there is only one lane, San Boldo is a two-way street, and traffic is controlled by traffic lights. When those who go up pass, those who go down wait, and vice versa. The cyclists, logically, can not make these last 5 kilometers in a single turn, so they must wait for the next ones, until they reach the top. The road is open all year round, although it may be impassable if after a heavy snowfall the roadway is not free of snow. The spectacular nature of the place and the history it has makes it a place well traveled by tourists and cyclists, so if you're sightseeing in Veneto, you know!

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The current road replaced a steep path that was formerly and that reached the summit. Although the idea of ​​paving and tunneling the area to adapt the passage to motorized vehicles had been on the table since the late nineteenth century, the project was not carried out until the First World War. It was the Austro-Hungarian Empire that carried out the construction so that the logistics of armament was more accessible in the area.

Thus, the works of the current San Boldo Pass began in February 1914 under the direction of the engineer Giuseppe Carpenè. Prisoners of war, elders, children and local women were forced to participate in it. It is said that up to 1,400 people took part in the construction, which was completed in a record time of 100 days, hence its nickname of "The 100 day highway". Despite the extreme topography of the place, one of the requirements was that the maximum slope did not exceed at any time the 12th, so that the passage could be traveled by heavy artillery since it was a strategic route for the supply of fuel during the Second World War.