Grenzau Castle

Around 1210, Heinrich I von Isenburg had the castle built under the name Gransioie. A first documented mention from 1213 confirms conflicts between Isenburg and the rights of Laach Abbey. In 1324, the middle line of the Lords of Isenburg-Grenzau resided at the castle. In 1346, Archbishop Balduin of Trier conquered the castle during the Grenzau Feud. Despite a victory over the Koblenz militia, Philipp I had to acknowledge feudal lordship in 1347. Emperor Charles V granted Grenzau the city rights of Frankfurt. From 1439, the elder Salentine line of the Lords and Counts of Isenburg inhabited the complex, which Gerlach II regained from Kurtrier in 1460. In 1557, the younger Salentine line strengthened the fortifications with gun bastions and a rondel. During the Thirty Years' War, the castle was set on fire by French troops on March 14, 1635. After the death of Count Ernst von Isenburg-Grenzau in 1664, the heavily damaged castle reverted to Kurtrier.