18. Vajont Dam, Italy
Built: 1957-1959
Collapsed: 1963
Est. Damages: Unknown
Originally conceived in the 1920s, it took more than 30 years for the idea of Italy’s Vajont Dam to come to fruition. Built between 1957-1960, the dam was in the final stages of its initial filling when, on October 9, 1963, a landslide occurred and caused one of the worst structural disasters Italy has ever seen.
Vajont Dam, Italy @Alicia Lage / Pinterest.com
A wave of, approximately, 820-feet in height was formed when more than 1.7 billion cubic feet of water toppled over the dam and rushed towards the Piave Valley. Nearly everything in the mega-tsunami’s immediate path was destroyed instantaneously upon impact. The exact number of casualties is unknown, however, it’s believed that up to 2,500 souls lost their lives that day.