This landmark is located on a hill to the west of the village of Silz. There is a pond to the south of the castle and the towering, five-story square keep is crowned with battlements. Beyond the castle is the so-called "Schnitzer Tower", also known as the "Faul Tower", which was originally the seat of the burgraves.

The castle was originally an estate or imperial fief owned by the House of Welf and was the centre of the earldom in the Oberinn Valley. St Petersberg was first mentioned in documents dating back to 1090/97 and was referred to as "Neuhaus" (new house) in the 12th and 13th centuries. Today, the castle is home to an all-male monastery and a convent is located at the foot of the Petersberg. The castle is privately owned and can only be viewed from the outside.