The Roman camp of Bonn was by far the longest used Roman base of the Lower Germanic Limes and therefore had special significance in the nomination application. The former legionary camp is located in the Bonn-Castell district. The ground plan and street layout of the Roman camp are still recognizable there in the modern cityscape. 

The Lower Germanic Limes was one of the most important borders of the Roman Empire. 400 kilometers long, it stretched from Remagen to Katwijk on the North Sea and existed for more than 450 years. Its unique archaeological monuments illustrate in a special way the development of a border of the Roman Empire and the life and cultural exchange in its surroundings.