Over 800 years ago, the Dukes of Zähringen built Thun Castle, Thun’s landmark, which still stands today. They never lived there—the castle served purely as a symbol of power and for representation. It is inhabited today—albeit temporarily—by those staying at Hotel Schlossberg. The former prison, with its modern inner courtyard façade and bay windows, blends gently into the historic, listed structure. Next to the hotel, in the new castle, the restaurant, conference rooms and museum were also opened in 2014. CTA supplied the room air conditioning units and cold water production for the kitchen, restaurant and conference rooms.