Switzerland

Grande Dixence Dam - 2
   This is listed by Wikipedia as the tallest concrete gravity dam in the world at 285m high and at an altitude of 2,365 metres, although there is currently a taller dam at Nurek in Tajikistan which is 300 metres. Visitors can take a guided tour inside the dam to explore some of the maintenance tunnels, and also take a cable car to the top where this photograph was taken. The dam holds back a lake, the Lac des Dix, which is usually full of water by late September, and empties during the winter, reaching its lowest point around April. This photograph was taken from the eastern end of the dam in June, when the water level was still low, as can be seen from the lighter coloured 'tide mark' on the surrounding rocks.
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Flags of the Valais