Vajont Dam

The Vajont Dam closes a deep, narrow gorge under Monte Toc in the Carnic Prealps, about 100 km north of Venice. It is a double-arch concrete dam 262 m high, among the tallest dams in the world, built between 1957 and 1960 by the Società Adriatica di Elettricità to the design of the engineer Carlo Semenza. As a piece of engineering it is breathtaking: a pale curved wall wedged between sheer rock faces, meant to be the heart of a network of reservoirs and tunnels feeding power stations in the Piave valley.

It is also the site of one of Europe's worst man-made disasters. While the reservoir was being filled, the mountainside of Monte Toc showed ever clearer signs of moving, and warnings from experts and from the villagers of Erto and Casso were set aside. On 9 October 1963 a huge landslide slid into the lake. It pushed some 50 million cubic metres of water over the crest in a wave about 250 m high, which fell into the Piave valley below and destroyed Longarone and neighbouring villages; around 2,000 people died. The dam itself survived almost intact, which is why it still stands today above a reservoir basin filled with the debris of the slide. In 2008 UNESCO cited Vajont as one of five cautionary tales of failures by engineers and geologists.

The place is now a memorial as much as a structure. Since 2002 guided tours have taken visitors onto the walkway along the crest, and the landslide area behind the dam has been open to visitors since 2007; the scar of the slide on Monte Toc and the mass of rock that filled the basin are still plain to see. Below, in the rebuilt Longarone, the memorial church by the architect Giovanni Michelucci stands among modern houses. The hydraulic scale model of the basin built before the disaster, at Nove near Vittorio Veneto, can also still be visited.

Getting there

The dam lies in the municipality of Erto e Casso, above Longarone in the Piave valley. Belluno is about 16 km away. The nearest airport is Treviso (TSF), about 70 km to the south.