Porta Nigra
Germany
The Porta Nigra (Latin for black gate), referred to by locals as the Porta, is a large Roman city gate in Trier, Germany. It is a monumental gateway representative of Hellenistic military architecture of the time. It is a UNESCO World Heritage Site. The name Porta Nigra originated in the Middle Ages due to the darkened colour of its stone; the original Roman name has not been preserved.
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