Appleby Castle is in the town of Appleby-in-Westmorland overlooking the River Eden. It consists of a 12th-century castle keep which is known as Caesar's Tower, and a mansion house. These, together with their associated buildings, are set in a courtyard surrounded by curtain walls. Caesar's Tower and the mansion house are each recorded in the Nat…Appleby Castle is in the town of Appleby-in-Westmorland overlooking the River Eden. It consists of a 12th-century castle keep which is known as Caesar's Tower, and a mansion house. These, together with their associated buildings, are set in a courtyard surrounded by curtain walls. Caesar's Tower and the mansion house are each recorded in the National Heritage List for England as a designated Grade I listed building. The uninhabited parts of the castle are a scheduled ancient monument.