The hill castle stands about 50 metres above the Lahn on a projecting hillside in the parish of Schadeck that was named after it within the borough of the small Hessian town of Runkel.

Because of inheritance and ownership disputes, Schadeck was built by Henry of Westerburg from 1276 to 1288 as a counter-castle to Runkel Castle, which at that time was owned by a cousin.

On 21 July 1321, an agreement was signed that forced the then Lord Reynard of Westerburg to hand over Runkel Castle as a fief to the Archbishop of Trier, Baldwin of Luxembourg.

From 1821, the west wing housed the mayor's office of the municipality of Schadeck and, in about 1850, the village school was located on the second floor.

The most important component of the present castle site is a well-preserved, 3+1⁄2-storey, rectangular building, which has a staircase tower on the western side.