The remains of the Castle can be visited
CastleMalta
Sonnenburg Castle

The documents are silent about the origin and fate of this fortified building, so one can only rely on assumptions. The builders of this castle were possibly Count Udalschalk, who is documented here in the 11th century, or the Lords of Mallentein, an assumption that has much in its favor.
Source: wehrbauten.at · Image: http://www.wehrbauten.at/ktn/kaernten.html
Text and/or image for this object come from the linked site and are used with the permission of its operators; the linked page remains the copyright of its authors. The legacy catalogue kept text source and image source in a single field, so which part came from there can no longer be told apart entry by entry.
Location: 46.9657, 13.4879