Vajont Dam

Where it sits. The Vajont Dam spans a gorge so narrow it is almost a slot, where the Vajont torrent cuts down to meet the Piave about a hundred kilometres north of Venice, in the Dolomite foothills between the Veneto and Friuli-Venezia Giulia. The wall is a double-curvature arch of concrete 262 metres high, one of the tallest dams ever built and the tallest in the world when it was finished. It is reached by the SS251 road, which climbs in tight bends from Longarone and passes straight through a tunnel in the abutment. Above and behind it, on the southern flank, is Monte Toc, whose face carries an enormous grey scar visible from kilometres away. The reservoir the dam was built to hold no longer exists: the basin behind it is filled to within a few dozen metres of the crest by rock, and you can walk across a valley floor that was once deep water.

What happened here. SADE, the private electricity monopoly of north-eastern Italy, conceived the scheme in the 1920s and built the dam between 1957 and 1960 to the design of the engineer Carlo Semenza. Geologists had warned that the southern slope was unstable; local people already called the mountain Toc, from a dialect word meaning rotten. Warnings and adverse reports were suppressed or minimised as the reservoir was filled, even as cracks opened on the slope and the ground crept downhill by centimetres a day. On the night of 9 October 1963, around 270 million cubic metres of the mountain broke away and slid into the lake in well under a minute. The displaced water rose some 250 metres above the crest and pushed roughly 50 million cubic metres over the top of the dam and down into the Piave valley. Longarone was effectively erased in minutes, along with the villages of Pirago, Rivalta, Villanova and Faè; between 1,900 and 2,500 people died. The dam itself barely moved, and stands today essentially undamaged: a structure that worked perfectly and killed thousands anyway. Trials, appeals and decades of argument followed, and the Vajont has since become a standard case study in engineering ethics worldwide.

On screen. The disaster reached a mass audience not through cinema but through theatre and television. On 9 October 1997, the thirty-fourth anniversary, the actor Marco Paolini performed Il racconto del Vajont — a monologue he had developed with the director Gabriele Vacis, built from testimony, court documents and dialect — live on RAI 2 from the top of the dam itself, standing in front of the wall in the dark. It drew several million viewers and did more than any inquiry to fix the event in Italian public memory. A feature followed in 2001, the Italian-French docudrama Vajont — La diga del disonore, directed by Renzo Martinelli, which reconstructed the wave with models and digital effects while shooting in the real valley. Documentary crews return constantly, and the site is one of the few places in Europe where a film location, an industrial monument and a mass grave are the same object — which is worth remembering before pointing a camera at it.

What you actually see today. The dam is owned by ENEL, disused, and partially open to the public since 2002. Guided tours cross the walkway along the crest, where the drop on the downstream side is vertical and the upstream side gives directly onto the rubble that replaced the lake; the tunnel galleries in the abutment are included on some visits. A visitor point at the dam explains the geology and the sequence of the collapse. Above, the villages of Erto and Casso survive; Erto's old centre was evacuated and stands half-abandoned in stone, and the path between the two settlements gives a plan view of the slide. Down in the valley, the monumental cemetery at Fortogna holds identical stone markers for the victims, and Longarone's church, built by Giovanni Michelucci between 1966 and 1978, is a striking piece of post-war architecture designed as a memorial in itself. The annual Sentieri di Memoria walk, inaugurated in 2006, opens routes across the site.

Getting there and timing. Longarone-Zoldo station on the Venice–Calalzo line is the rail access, with Belluno half an hour south; by road, the SS51 from Belluno then the SS251 up the gorge. Guided tours run mainly from spring to autumn and are largely in Italian, though the visitor centre has material in English and German. Allow half a day for the dam, Erto and the cemetery together. The gorge holds cold air and shade well into the morning; light on the wall is best in the middle of the day. Note that the site remains a place of mourning for the surrounding communities, and behaviour on the crest is expected to reflect that.