The remains of the castle can be visited
Oberburg Castle

The Oberburg castle ruin, also known as Altenburg, is a hilltop castle above the municipality of Kobern-Gondorf.
History+
The origins of Oberburg date back to the early 12th century, when it was built on the foundations of Celtic fortifications. Its first documented mention occurred in 1195, when the then lord of the castle transferred the property to the Archbishop of Trier as a fief. Between 1220 and 1240, Knight Heinrich II von Isenburg had the St. Matthias Chapel built to house a relic, the head of the Apostle Matthias. The Lords of Isenburg-Kobern owned the castle until the mid-14th century, before it was sold to the Archbishop of Trier and subsequently fell into disrepair.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=612
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: 50.3143, 7.4537