The Plastiras Dam is a concrete arch dam in Karditsa Prefecture, Greece that impounds the Tavropos (Megdovas) River, creating an artificial lake respectively called the Lake Plastiras.

The building was officially founded on December 14, 1955, and the construction lasted for almost five years. The dam was dedicated on October 30, 1960. Plastiras Dam is an arched dam made of concrete, blocking a narrow point known as Kakavakia. The dam is elevated 795 m (2,608 ft) from sea level. It stands 83 m (272 ft) high and has a crest width of 220 m (720 ft). Its overall volume is 100×103 m³.
(from Wikipedia)

Couldn't have said it better myself. All I can add is:
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