Longarone, Veneto, Italy
427 feet high / 130 meters high
(98) foot span / (30) meter span
With a height to span ratio of at least 4:1, the Colomber arch crossed above the Vajont River in a way that was likely described with such rarely used words as ‘abyss’, ‘crevasse’ and ‘bottomless’. Of course that all ended in the 1950s when construction began on the Vajont dam, creating a reservoir that would forever submerge the location of the Colomber bridge. Before the reservoir was completely filled, a massive slide occurred on the night of October 9th, 1963 when 150 million tons of the mountain descended into the reservoir. Millions of tons of water thundered over the top of the dam and down into the gorge toward the towns of the Piave River valley 1 mile (1.6 km) away. The people never had a chance when a wall of water 200 feet high (61 mtrs) wiped everything out, killing more than 2,000 Italians. Today, when people think of the Vajont River canyon, they think of little else outside of the towering dam and the destruction it indirectly caused. Today the reservoir is still there, kept at a level much lower than intended but still high enough to keep the Colomber bridge site hidden from view.
This image shows a less permanent Colomber bridge constructed before or after the arch.