The remains of the Castle can be visited
Falkenstein Castle

The Falkenstein Castle Ruin overlooks the village of the same name in the Donnersberg district of Rhineland-Pfalz.
History+
The first documented mention of Falkenstein Castle occurred in 1135, when it was owned by the Lords of Falkenstein, a collateral line of the Lords of Bolanden. In 1233, the castle belonged to Philipp I of Falkenstein, who held an important position as imperial chamberlain and castellan of Trifels. After the extinction of the imperial chamberlains of Münzenberg, Philipp I assumed their office and inherited the Landvogtei in the Wetterau in 1255, with Lich becoming the center of his dominion. Around 1500, Uhland I expanded the castle.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://www.wehrbauten.de/thread.php?threadid=1343
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: 49.6092, 7.8738