The remains of the Castle can be visited
Cartatscha Castle (Ruin) (Trun)

The Cartatscha ruin, a former hilltop castle, stands on a moraine ridge above Trun in the Swiss canton of Graubünden.
History+
There are no written records regarding the exact origins and history of Cartatscha Castle. Based on its construction style, it is assumed to have been built in the 13th century. It is believed to have served as the seat of a ministerialis or bailiff of the Disentis Monastery, possibly Olricus de Crestazia, mentioned in 1261. When the castle was abandoned is unknown. The current state of the ruin suggests a planned demolition, as debris is absent and the walls are cleanly horizontally delimited.
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: 46.7478, 8.9869