The roman Temple can be visited
Roman Temple Pesch

The Roman Temple District of Pesch, often referred to as the Heathen Temple, is a Gallo-Roman cult site in North Rhine-Westphalia. The complex is situated on the “Addig” hill between Bad Münstereifel-Nöthen and Nettersheim-Pesch and is today the best-preserved Roman cult site in the region.
History+
The origins of the temple district date back to the 1st century AD, with its heyday in the 4th century. Archaeological excavations between 1913 and 1918, supplemented by further investigations in 1962, uncovered the foundations of this complex. Originally likely a tree cult site, it developed into a matron sanctuary dedicated to the Matronae Vacallinehae, Celtic-Germanic mother goddesses. Numerous dedicatory inscriptions attest to the veneration of these patronesses of a local clan. The temple district reached its greatest extent in the 4th century with an east-west oriented rectangle measuring 100 by 34 meters, before its destruction in the early 5th century. The remains visible today reflect the last of three construction periods; earlier wooden structures and older phases are not represented in the reconstruction.
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: 50.5335, 6.7030