The Roman Castle can be visited
Roman Castle CAMBODVNVM (Camboduno)

The Roman fort CAMBODVNVM in Kempten, Bavaria, is one of the most significant Roman settlements in the province of Raetia. The complex on the Lindenberg, an ice-age gravel terrace, was once a city and possibly the first provincial capital before Augsburg.
History+
The Roman settlement of Cambodunum emerged shortly after 15 BC, when Drusus and Tiberius brought the pre-Alpine region under Roman rule. Its location on important long-distance roads, which connected to Italy, Lake Constance, and the Danube, fostered its prosperity. The first wooden buildings are traceable from the reign of Tiberius, with stone buildings following from the Claudian era. The city reached its peak in the 1st century, manifested in the construction of a forum with a basilica and a Gallo-Roman temple district. By the end of the 3rd century at the latest, the settlement on the Lindenberg was abandoned due to pressure from invading Germanic tribes.
Source: Wikipedia · Licence: CC BY-SA 4.0
This description draws on the facts documented in the linked Wikipedia article; Wikipedia content is licensed under CC BY-SA 4.0. Wording and editing: Mobile History.
Location: 47.7267, 10.3265