The Staircase Tower The oakwell staircase off the Anne Boleyn Room is an antique work of art in itself. One of a kind, it boasts separate newel posts decorated with finials at their apexes – a popular style around 1600. On the second floor, a spiral stairway winds to a tower room and the roof of the tower. At the head of the stairs, an historic plaque hints of a connection between Great Fosters and Henry Percy, 9th Earl of Northumberland, who was imprisoned in the Tower of London for 15 years following his implication in the famous Gunpowder Plot of 1605.