The Porta Praetoria in Regensburg stands as a remarkable testament to the city's ancient past. Constructed in the 2nd century AD, this north gate of the Castra Regina legionary camp is one of the few surviving Roman gates north of the Alps. Its discovery in 1885, after being concealed within the walls of a brewery, has provided invaluable insights into Roman military architecture and the strategic significance of Regensburg during the Roman Empire. Today, it serves as a tangible connection to the city's storied history and its evolution from a Roman military base to the vibrant urban center it is now.