"The Castle" was built in 1858 by General Copeland, the original owner of the campus. It has had many reinventions, including a stint as the Orchard Lake Hotel, astronomical observatory, and the residence of the Chancellor of the Orchard Lake Schools. It has 10 rooms total; including 6 bedrooms, a conference room, and 3 apartments. As a hotel, it once had 2 wings that could accommodate 100 people. Although it is no longer used as a residence for the OLS Chancellor, famous guests have included St. John Paul II during his 1969 and 1976 visits to the campus.