Niedernberg's beginnings go back to one such castrum, built between 83 and 150, at the so-called “Wet Limes”, which stood as the Empire's eastern border. The castrum, which measured 144 by 135 m, was built facing the east, towards the Main. Although the castrum was later overbuilt, the way the core of the community is laid out still goes back to the street layout in the castrum; "Hauptstraße" (“Main Street”) and "Kirchgasse" (“Church Lane”) correspond with streets in the Roman camp. Niedernberg was the post of a 300-strong cohort, "Cohors I Ligurum et Hispanorum", which drew its recruits from northern Italy and Spain.