St Andrews Castle, Fife
Not far from the cathedral and with dramatic coastline views, St Andrews Castle is mainly in ruins, but the site itself is evocative. The most intriguing feature is the complex of siege tunnels, said to be the best surviving example of siege engineering in Europe. You can walk along the damp, mossy tunnels, now lit by electric light – but be warned, it helps if you’re short. The Castle was founded around 1200 as the fortified home of the bishop.
St Andrews Castle and its siege tunnels are a must see on your tours of Scotland.