The remains of the Castle can be visited
Schwarzenfels Castle (Ruin)

The Schwarzenfels Ruin, a 13th-century complex, features a portal from the early 17th century. The first documented mention of Schwarzenfels Castle dates back to 1280. Through an inheritance, it passed from the House of Rieneck to the County of Hanau in 1333 and served as an imperial fief and administrative center for the Schwarzenfels district. In later periods, the complex was converted into a residential castle, evidenced by the portal from 1621. The Counts of Hanau repeatedly used Schwarzenfels as a dower house. Following inheritance disputes, the castle was awarded to Count Albrecht, whose lineage was subsequently named “Hanau-Münzenberg-Schwarzenfels,” though it died out in the very next generation. During the Thirty Years' War, the castle was destroyed and the core castle abandoned. In 1643, it was pledged, along with the Schwarzenfels district, to the Landgraviate of Hesse-Kassel to secure unpaid war costs.
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: 50.3003, 9.6711