The remains of the castle, which was after 1945 senselessly destroyed, can be visited.
Blankenberg Castle (Ruin)

The Blankenberg Ruin, once part of a chain of defensive fortresses along the Saale, stands on a rocky outcrop. Although deliberately destroyed after 1945, its remains are now an accessible site in the Saale-Orla district of Thuringia.
History+
Originally an imperial fief, Blankenberg Castle changed hands multiple times. The assumption that it was built as a coercive castle against the Sorbs is now considered unlikely. Instead, it is presumed that its origin dates back to the era of the Staufer-Welfen conflicts. Emperor Frederick I is believed to have built castles like Blankenberg on the right bank of the upper Saale to protect the Egerland from Welfen attacks and to secure the newly established Vogtland. The castle lost its military significance and was transformed into a palace, where living comfort took precedence over defense. The building remained largely intact until the end of World War II. In the course of land reform and Order No. 209 of the Soviet occupation forces, Blankenberg Castle was blown up on June 14, 1948. From 1995 onwards, citizens became involved in uncovering and restoring the ruin.
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: 50.4009, 11.7152