Stirling Castle sits atop Castle Hill, which is surrounded on three sides by steep cliffs (making it a very good location for defense). Much of the castle was built in the fifteenth and sixteenth centuries, although a few structures do date back to the fourteenth century.
Before Scotland’s union with England, Stirling Castle was a Scottish royal residence (as well as a fortress). Multiple Scottish Kings and Queens were crowned at Stirling, including Mary, Queen of Scots, in 1542.
See the Stirling Heads Post for more interesting history of this castle.