Covao dos Conchos: A Portal to Nature’s Wonders in Portugal’s Serra da Estrela
High up in the Serra da Estrela mountain range in Portugal, there lies a lake with an unusual man-made marvel. From a distance, an inverted bell-shaped drain known as Covao dos Conchos, constructed in 1955 as part of a hydroelectric dam, appears to be a perfectly symmetrical whirlpool, the mouth of a hungry sandworm, or…