A massive landslide from Monte Toc in the Belluno Alps in Northern Italy, plunges into the artificial lake in the Vaiont Gorge behind the Diga del Vajon dam; creating an immense wave of water to rise as high as 300 feet above the level of the dam and into the Piave River flooding the valley below, engulfing the town of Longarone.
Within minutes the town had almost vanished killing nearly 2,000 people the wave of water then rushed down to San Martino, where it killed hundreds more. The dam itself was almost totally undamaged and two-thirds of the water was retained behind it.
