The long wall is a Roman fortification from the 4th century, which was built under the late Roman Emperor Valentinian I (364 - 375 AD).
The wall had a total length of about 72 km and was supposed to protect a late antique imperial domain area, which covered an area of about 220 km². Two donations from the Frankish king Dagobert I from the 7th century prove that the imperial domain later became the property of the Frankish kings.
The exact protective function of this wall is not clear nowadays. Since the fortifications had a maximum height of about two meters, it is assumed that they served more to protect against invading game than for purely military purposes. This thesis is supported by the fact that the wall encloses an area with limestone soils that is one of the most fertile in the Trier region.
Several villae rusticae located within the wall district or nearby probably had the task of supplying the imperial court in Trier (Augusta Treverorum). These include the Villa rustica Newel and the Villa Welschbillig. The latter is known for the magnificent “Hermenweiher”, a basin in front of the main front of the complex, on which 112 herms by ancient personalities were set up. The pieces are now in the Rheinisches Landesmuseum Trier. In the Middle Ages, a castle of the Trier electors was built on the ruins of the villa. Post-Roman history is thus very similar to that of the Palatiolum in Trier-Pfalzel.