Castra Bonnensia

fortress, Bonn, Germany

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June 24, 2026

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Castra Bonnensia was a Roman fortress established in the 1st century CE in what is now Bonn, Germany. This Roman settlement originated from a river crossing discovered by legionnaires. Although the original settlement may have disappeared, the name persisted with the construction of the fortress. Castra Bonnensia endured beyond the Roman Empire and evolved into the Frankish town of Bonnburg by the 9th century. Bonn itself later became the capital of the Electorate and Archbishopric of Cologne before becoming the provisional capital of West Germany from 1949 to 1999.12

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…its name was continued in Castra Bonnensia, a fortress built by the Romans in the 1st century ce. Castra Bonnensia survived the breakup of the Roman Empire as a civilian settlement, and in the 9th century it became the Frankish town of Bonnburg.
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…its name was continued in Castra Bonnensia, a fortress built by the Romans in the 1st century ce. Castra Bonnensia survived the breakup of the Roman Empire as a civilian settlement, and in the 9th century it became the Frankish town of Bonnburg.
Read More