Roman Castle Arnsburg (Lich)

Initially built as a wood-and-earth camp in the second half of the 1st century, Arnsburg-Alteburg Fort was already secured by enclosing walls at the beginning of the 2nd century, following the Roman rectangular scheme with four gates, each secured by two towers. The main gate, designed as a double gate with two additional towers, was located on the eastward-facing narrow side. In addition, the complex was protected by 14 further towers on the ramparts.

The area, with side lengths of approximately 185 and 160 meters and a circumference of 699 meters, was only slightly smaller than Saalburg with 737 meters and Butzbach Fort with 732 meters. This area provided space for a Roman cohort, i.e., for a troop of about 600 men, and all necessary internal stone buildings such as the headquarters (Principia), the commander's residence (Praetorium), and the granary (Horreum). Near the main gate, remains of a large building were found, probably a manor house or an inn (Mansio).

In the Principia, the remains of an armor clasp were found; garment fragments were found in the fort area. All these remains belonged to one or two large bronzes dating to the first half of the 3rd century.

Fort and Limes

The history of Arnsburg-Alteburg Fort begins in the second half of the 1st century during the time of the Roman Emperor Domitian, a period when the Chatti advanced southward from northern Hesse and established a strong position against the Rhine frontier of the Roman Empire. Domitian, still intent on expanding the Roman Empire, then launched a campaign against the Chatti in 83 AD with great military effort, with the result that, although they were not overcome, they could be pushed back. The now unprotected Wetterau again offered the Romans the opportunity to advance far north and northeast from their base in Mainz, thus keeping the Chatti out of their area. For this purpose, they used a multitude of simple military camps along the newly created frontier line, including at the confluence of the Welsbach with the Wetter river, which gave the landscape its name. In the following more peaceful decades, numerous manor houses were built in the fertile Wetterau to also use the area agriculturally. The military camp on the Wetter was initially greatly enlarged and finally moved to a neighboring high plateau called Alteburg and provided with ramparts.

In the course of the final border demarcation carried out around the year 90, the Romans fortified the military camps located at strategically favorable places and expanded them into forts, according to the requirements of the Limes, including the Alteburg camp. The Limes, whose course in the Wetterau is still well discernible over longer stretches, projected wedge-shaped to the north from the Taunus, via Saalburg and Butzbach to Grüningen, where it reached its northernmost point right of the Rhine. From here, it ran southeast past Alteburg Fort to Inheiden Fort and further to the Main to Großkrotzenburg Fort.

The Limes was subject to constant expansion. Near Alteburg Fort, there were extensions of the ditches and reinforcements of the ramparts over longer stretches even in the 3rd century. In the years 250 to 260, the Romans abandoned the Limes and its associated facilities (Limesfall). Alteburg Fort was abandoned and left to slow decay. The area disappeared from historical view during the Migration Period and reappeared only in 1151, but then under the name Arnsburg.

Subsequent Use

After the abandonment of the Limes, Franks settled the Wetterau. The Roman fiscal land was systematically recorded, and numerous new settlements emerged along the old Roman roads by 800. This resulted in a concentration of royal property in the former Limes area.

In the immediate vicinity of the abandoned Alteburg Fort, two castles were built successively: a smaller one northeast of the fort, dated to around 800, and a second one, 600 meters southeast of the fort remains on the Hainfeld, whose origin is estimated to be around 1000. The latter was abandoned in favor of Münzenberg Castle, and the castle and the surrounding land, including the fort ruins, were handed over to the Benedictine order for a monastery foundation, which they undertook on the fort grounds but abandoned as early as 1174. In the same year, Kuno I von Münzenberg transferred Arnsburg Castle, the fort with the commenced monastery church, and all lands in the Wetter valley to Eberbach Monastery, which sent monks who immediately began the new construction of a monastery church, this time, however, in the Wetter valley bottom, below Arnsburg Castle. Arnsburg Monastery was built here.

All users of the site following the Romans used the Roman fort as a quarry. In 1904, the Butzbach-Licher railway – now abandoned – was laid at the edge of the fort area. The route largely bypassed the central findings.

The fort's garrison consisted of partially mounted units. The first known troop in Arnsburg was the Cohors II Aquitanorum equitata (2nd partially mounted cohort of Aquitanians), originating from Aquitaine. The oldest proof of its existence is secured by two military diplomas, which attest to its presence in the province of Germania superior (Upper Germany), to which Arnsburg belonged, on September 19, 82, and October 27, 90. Between 107 and 116, the unit was transferred to the province of Raetia (Raetia) and quartered in the Regensburg fort of Kumpfmühl until the Marcomannic Wars (166–180). It was followed in Arnsburg at the beginning of the 2nd century by the Cohors I Aquitanorum veterana equitata (1st partially mounted veteran cohort of Aquitanians). When this veteran cohort was transferred to Stockstadt Fort after the middle of the 2nd century, the Cohors V Dalmatarum (5th cohort of Dalmatians), also known from Heilbronn-Böckingen Fort, took its place in Arnsburg. A soldier of the 5th Dalmatian cohort stated his hometown as Municipium Doclea, located in present-day Montenegro. This city then belonged to the province of Dalmatia.

The auxiliary troops mentioned, as their names explain, were assembled in Aquitaine and Dalmatia and had to serve far from their homeland. Later, these units also recruited soldiers from among the male population of the provinces where they were stationed. The cohorts were subordinate to Legio XXII Primigenia in Mainz.

Arnsburg Fort has been part of the UNESCO World Heritage since 2005 as a section of the Upper Germanic-Raetian Limes. It is also an archaeological monument within the meaning of the Hessian Monument Protection Act. Research and targeted collection of finds require permission, and accidental finds must be reported to the monument authorities.

In 2005, the Archaeological Society in Hesse succeeded in purchasing the entire fort area, including the Vicus, for 120,000 Euros as part of a land consolidation, removing it from agricultural use, and thus permanently securing the cultural monument. Several information boards have since explained the archaeological monument.

Until 2015, technical methods such as ground-penetrating radar are to be used to search for further hidden remains of the fort's buildings. There will be no excavation activities on the site before the completion of this prospecting. It is also conceivable to leave the archaeological monument as such after its complete recording.