Complex sentence: Loch Leven Castle lies on an island a short way offshore, where Mary, Queen of Scots was imprisoned in 1567, and it can be reached by ferry, operated from Kinross by Historic Scotland during the summer months.
Split into simpler sentences: Loch Leven Castle lies on an island a short way offshore. The castle was the prison of Mary, Queen of Scots, in 1567, and it can be reached by ferry, operated from Kinross by Historic Scotland during the summer months.