[3] From tile stamps it appears that from AD 88-89 until 275 the fort was manned by cohors II Hispanorum peditata, an auxilia infantry cohort of the Imperial Roman army.

[2] The fort contained the headquarters building, or principia, within a rectangular courtyard surrounded by a colonnade (portico).

This room and the atrium both held stone altars in period V.[2] A protective ditch surrounded the fort throughout its Roman occupation.

When the city began to build an underground parking deck in the early 1930s, its priorities changed after the remains of the castellum were discovered.

Roman artifacts and parts of the fortifications were found, as were partial remains of wooden barracks and traces of the moat.

[2] Beginning in 1992, the nearby Duitse Huis, headquarters of the Teutonic Knights' Bailiwick of Utrecht from 1348, was extensively renovated.

This included building a new wing of the Grand Hotel Karel V. Traces of a Roman cemetery were found, perhaps associated with the fort.