The Earl's Palace is a magnificent ruin immediately adjacent to St Magnus Cathedral. Patrick Stewart, 2nd Earl of Orkney, began building it in 1607, and despite its owner's thoroughly villainous reputation, the result is considered one of the finest examples of Renaissance architecture in Scotland. The great hall, the oriel windows, and the remains of the towers suggest something that was genuinely palatial before it fell into decay after the 1680s.
Historic Environment Scotland maintains the ruins as a protected scheduled monument. They are open to visitors (a modest admission applies) and can be combined easily with the Bishop's Palace ruins just across the road, which date from the twelfth century and include a round tower with views down over the cathedral roof.