Perched at the craggy edge of Castle Rock, the world-renowned Edinburgh Castle, with its brooding grey fortification, was once the military centerpiece of the British army in Scotland. Along with fulfilling its duties as a wartime fortress, it was also the residence of King Malcolm Canmore and Queen Margaret in the 11th Century. Within its dark grey walls and even beyond them, the Edinburgh Castle is home to some of the most marvelous relics of Scottish history, meriting it one of the most popular paid-attractions in the world. The oldest monument atop the volcanic Castle Rock promontory is St Margaret's Chapel, beside which Mons Meg, a colossal siege gun dating back to the 15th Century stands in historic pride. At the heart of the castle's main complex, one can almost hear the deafening silence of the Great Hall, the erstwhile site for several royal ceremonies and the place of congregation for the Scottish Parliament. A little further toward the east, the Royal Palace proudly displays the sparkling crown jewels and the Stone of Destiny. Together with its remarkable past and beautifully preserved elements of history, both Castle Rock and the Edinburgh Castle form solid units of Scotland's royal and political heritage.