The Porta Nigra is a large Roman city gate in Trier (Treves), the oldest city in Germany, founded in 16 BC. In Roman times, the Porta Nigra was part of a system of four city gates, one of which stood at each side of the roughly rectangular Roman city. The Porta Nigra guarded the northern entry to the Roman city.

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The Porta Nigra in the “Second Rome” ?