The Porta Praetoria is a Roman gate in Regensburg. Next to the larger and more completely preserved Porta Nigra in Trier, it is the only remaining Roman gate north of the Alps.
The Porta praetoria was the main gate of military camps in Roman antiquity, it was usually on the side of the camp facing the enemy. The Porta Pretoria in Regensburg was part of the fortification of the legionary camp Castro Regina which was completed in 179 AD. under Emperor Marc Aurel. The city of Regensburg emerged from this camp, the gate itself was built over in the High Middle Ages, partially destroyed in the process, and only rediscovered in 1885. You can still walk through one of the archways and get into the courtyard of the Bischofshof Regensburg, now a hotel and a very good restaurant with a nice beer garden.
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