Porta Nigra · The Colour of Its Own Stone

The Porta Nigra in Trier is a city gate from the Roman Empire, built of enormous sandstone blocks without a drop of mortar, held together by iron clamps and their own weight.

In the Middle Ages it was converted into a church, then fell into disuse; in Napoleon’s time it was partly taken down and partly rebuilt. Today it is the most complete Roman city gate in Germany. The name “Black Gate” comes from the colour the stone turned as it oxidised over the centuries.

What the Romans threw in here, or whom they held here, no one can reconstruct. Standing under the gate and looking up, the joints between the stones are too fine to take a knife blade.

Historical Mysteries / Trier · Germany / 170