Always wanted to visit this place and my wish finally came true during this trip. San Boldo Pass (Passo San Boldo) in Northern Italy. This is a small mountain pass in Veneto between the towns of Trichiana and Tovena over a distance of 17 km in length. The mountain pass is called the SP 635 and only one lane is passable, traffic being regulated by sets of lights. Speed limit is set at 30km/h and a height limit of 3.2 m, after buses were repeatedly stuck in the tunnel. There are five tunnels blasted into the rock with hairpin turns or loops, and six bridges. Austro-Hungarian army built the road from February to June 1918 as part of its World War I logistical efforts. The road to supply the front was built in only three months. Due to its short construction period, it is nicknamed the "Road of 100 Days." Prisoners of war, the elderly, women and children of the local population were pressed into service to build it. In its final construction phase, 1,400 workers worked in three shifts to build this strategically important connection. Despite the extreme topography, the requirement that the road be used for transporting heavy artillery and supplies meant that the grade could not exceed 12%.