Finkenstein Castle is a ruined medieval castle in the market town of Finkenstein, in the Austrian state of Carinthia. It is situated on a steep cliff at the southern foot of the Karawanks mountain range, high above Lake Faak, at a height of 788 metres. Today the castle ruin is the backdrop of the Burgarena, an amphitheatre with 1150 seats mainly used for concerts and festivals.