The Tower of London is one of the most historic sites in all of England, and still one of the most popular. All around is the modern City of London, one of the world's most prosperous and power financial districts, but the Tower is still a daunting structure that looms across the landscape. Not a single structure but a vast network of medieval and early modern fortifications, it anchors the southeastern end of the old City and controls access to the River Thames and, through it, London's connection to the sea. While the both the City and the Thames are often obscured by the walls once visitors are inside the Tower, they are inextricably tied to the building, giving the Tower its entire reason for existence. Even today, taking a tour of the Tower can seemingly bring its history to life. Inside the visitor center are replicas of a crown, an executioner's axe and similar artifacts, but for most visitors, this is just the start. After they cross a small courtyard and approach the first gate, known as the Middle Tower, they come to a stone bridge over a now-dry moat and enter the castle itself through the Byward Tower. The Tower, like many fortresses of its day, was built in concentric rings, so inside the outer wall is a narrow strip of land before the inner walls. Long, narrow buildings line the inside of the outer wall, and to the left along Mint Street these structures once housed the operation of the Royal Mint, making all of the coins of the realm. From there, most visitors continue straight along, typically guided by one of the colorfully-dressed Yeoman Guards (the famous "Beefeaters"). Under the watch of the Bell Tower, they continue along the south face of the inner wall, on Water Lane, and just ahead is the famed Traitor's Gate; while today the area around here is paved and dry, in earlier times this was a "watergate" that allowed boats entry to the fortress. It was so named because this was the entrance by which prisoners (often traitors) entered the fortress, often never to leave. Ahead is Wakefield Tower, the entrance to the inner courtyards and a space that can be rented for small banquets and private dinners. Inside the inner courtyards, visitors get a good first look at the White Tower, the 11th century Norman castle at the heart of the Tower (and the original "Tower" the entire complex is named for). Built of distinctive white stone, it has been a beacon of royal power for centuries. It is four stories tall and at points has walls of up to 15 feet thick, with towers on the four corners that have cupolas atop them (added much later than the original structure). Within the Tower is an impressive collection of medieval armor and arms, as well as the well-preserved St. John's Chapel. Directly behind the White Tower is the Waterloo Block, also known as the Jewel House. A perennial favorite of visitors, the Crown Jewels of the United Kingdom are stored here when not in use. In the southeast corner of the inner courtyard (the "Inner Ward") is a charming green space backed by lovely Tudor structures whose calm belies their bloody history. This is the Tower Green which was the location of the executions of all of those prisoners who were given "Private" deaths (as opposed to a "Public" death which occurred outside the walls on Tower Hill before the London mob). Ultimately, it's impossible to fully appreciate the Tower without understanding its context. Like all fortresses, it was built to control and protect its surroundings, and the history of the Tower is bound up in the mutual histories of London and the Monarchy. The unfolding saga of war, imprisonment, glory, and treason in England can all be told through the lens of the Tower, and the lives that intersected with it.