Birsay Earl's Palace in Orkney is the former residence of Robert Stewart, half-brother of Mary Queen of Scots. Built between 1569 and 1574, this courtyard castle is surprisingly intact, despite its turbulent history. Known for its gun holes in every wall, it seems like Stewart was ready for trouble! However, the palace fell into disrepair after the overthrow of the Stewart earls in 1615. Today, visitors can explore the ruins and get a glimpse into Orkney's past.