The remains of the Castle can be visited
Scharfeneck Castle

The castle ruin of Scharfeneck is situated on the Schwechat River near Baden bei Wien. It is characterized by its early settlement and the uncertain history of its abandonment, which was closely linked to the power dynamics of the region.
History+
Archaeological findings confirm that Scharfeneck Castle was inhabited as early as 1100. However, it was abandoned by the 13th century at the latest. It is presumed that the small complex lacked the economic foundation to assert itself against the neighboring castle of Rauheneck. A wide breach in a sidewall suggests deliberate destruction.
Source: Wikipedia · Licence: CC BY-SA 4.0 · Image: http://commons.wikimedia.org/wiki/File:ScharfeneckGrundmauerBresche-smaller.jpg
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: 48.0133, 16.1969