Welcome to the Royal Mile, the grand processional route that has served as the beating heart of Edinburgh for over eight hundred years. You are standing on a unique geological feature called a crag and tail, formed more than three hundred million years ago by retreating glaciers. This ridge connects two iconic symbols of power: the fortress of Edinburgh Castle at the top of the hill and the Palace of Holyroodhouse at the bottom. While we call it a mile, the street actually measures about one point eight one kilometers, which is equivalent to one Scots Mile—an ancient unit of measurement that was significantly longer than the standard English mile. As you begin your walk, notice how the city’s history is layered into the very stones beneath your feet, from medieval markets to the modern seats of government.