The remains of the Castle can be visited
Klingenhorn Castle (Ruin) (Malans)

The Klingenhorn ruin, a former hill castle, is at approximately 929 meters above sea level above Malans in the Swiss canton of Graubünden. Its location on a rock spur, which steeply drops into the Ülltobel, once gave it a strategically important position.
History+
The exact construction period of Klingenhorn Castle is not documented in writing but is presumed to be in the early 13th century. In the 14th century, the complex may have passed to the Matsch family through inheritance. A document from March 12, 1372, confirms that Ulrich II von Matsch pledged the castle to Ulrich von Underwegen, with the condition that it would remain an open house for the Matsch bailiffs. In 1420, the castle was uninhabited, as evidenced by a grant of estates on Klingenhornberg, which legally assigned the Malans court to the castle. Around 1470, Klingenhorn came into the possession of the Schlandersberg family.
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: 46.9942, 9.5796