The historic Tower of London is located on the north bank of the River Thames, within the London Borough of Tower Hamlets, separated by an open space known as the Town Hill from the eastern edge of the square mile of the City of London. Officially known as Her Majesty’s Royal Palace and Fortress of the Tower of London, and regarded as one of the most popular tourist attractions of the capital city, it has been a fortress, palace, armoury, prison, mint, jewel house, and home to both the ravens and Beefeaters, the Guard in the Tower. It resembled little more than a wooden shed on a hill surrounded by a garden fence, when initially built towards the end of 1066, by the Norman invaders from France.
Gradually, it grew over the centuries and took the shape of a complex of several buildings set within two concentric rings of defensive walls and a moat.
Enclosing a huge area of 4.9 hectares (49,000 sq m), with a further 2.4 hectares (24.00 sq m) around the Tower of London constituting the Tower Liberties, the castle is made up of three wards, or enclosures, encircled around the White Tower, the innermost ward which is the earliest phase of the castle, built by William the Conqueror in 1078, resenting the symbol of oppression, inflicted upon London by the new ruling elite. The inner ward that encircled the innermost ward to the north, east, and west, was built during the reign of Richard I, while the outer ward encompassing the castle was built under Edward I.
The White Tower, the nucleus of the innermost ward, was constructed mainly of Kentish rag-stone and measuring 118 by 105 feet (36 by 32 m) at the base, and 90 feet (27 m) high at the southern battlements, was originally three-storey high, including a basement floor, dimly lit through small slits, an entrance level, and an upper floor. While each floor was divided into three chambers, the largest was in the west, a smaller room in the north-east, and the chapel at the entrance and upper floors of the south-east. There is a larger semi-circular projection at the south-east corner accommodating the apse of the chapel. A smaller chamber to the east, leading to the approach to the upper floor, is also connected to the entrance floor. While the western corners of the building are square towers, the north-east is a round tower housing a spiral staircase.
The upper floor of the White Tower contained the St John's Chapel in the south-east, a grand hall in the west and residential chambers in the east. Originally, it was opened to the roof and surrounded by a gallery, built into the wall. While the chapel is currently bare and unadorned, during the reign of Henry III in the 13th century, it was adorned with a gold-painted cross and stained glass windows, depicting the Virgin Mary and the Holy Trinity.
The innermost ward enclosing an area immediately south of the White Tower was originally surrounded by a protective ditch, which was probably filled with timber buildings from the Tower's foundation. According to the available evidence, a great hall once existed in the south of the ward between two towers. Between 1666 and 1676, the palace buildings in the innermost ward were removed, the Jewel House was demolished, and the area around the White Tower was cleared to keep it safe from the stealthily approaching enemy.
The inner ward was created during the reign of Richard the Lionheart, when the size of the castle was effectively doubled, and a moat was dug to the west of the inner ward. The main entrance to the inner ward was probably through a gatehouse in the west wall on the site of the present Beauchamp Tower, which is one of 13 towers that stud the curtain wall, along with Bell, Flint, Bowyer, Brick, Martin, Constable, Broad Arrow, Salt, Lanthorn, Wakefield, and the Bloody Tower.
As the names suggest, Bell Tower housed a belfry to raise the alarm in the event of an attack, and the workshop in the Bowyer Tower was the royal bow-maker, producing longbows, crossbows, catapults, and other hand weapons, like swords, spear, and others. The Lanthorn had a turret at the top to signal unwanted approaching during the night. The walls of the Beauchamp Tower contain the writings and images created by the high profile aristocratic prisoners held in the tower, mostly confined for political or religious reasons, as their last messages before their execution.
The Bloody Tower, a simple structure, protected by a portcullis and gate, and located immediately west of Wakefield Tower, was built as a water-gate providing access to the castle from the River Thames. The simple structure, protected by a portcullis and a gate, has a dark history behind its naming, which it earned in the 16th century. It was believed that two young brothers, King Edward V, the rightful heir to the throne, and his younger brother, Richard, Duke of York, were allegedly murdered in the Tower, before the young king could be crowned, by their uncle Richard III, who became king in 1483. Sir Walter Raleigh, one of the most famous explorers during the reign of Queen Elizabeth I, was imprisoned here by King James I, and was beheaded in 1618.
The Salt Tower, one of the lesser-known buildings at the Tower of London, despite its to-die-for river view, was built for King Henry III, where the Scottish King John Balliol was imprisoned in the 1290s. Once a luxurious condiment, it was subsequently turned a place to store salt. The Constable Tower, one of the oldest in England, was named after the Constable of the Tower of London, who was the person in charge of the castle in the absence of the King. The ruinous Wardrobe Tower was built in the 1190s for King Richard the Lionheart, who hardly spent about six months of his ten-year reign in England.
The Martin Tower, made of uncalibrated stones joined with mortar, is actually a set of several buildings nested within each other. It is cylindrical, rests on a body of building slightly larger than the tower, and is accessed by the circular path which circles all the towers of defense of the first enclosure. After the demolition of the Jewel House in 1669, the Crown Jewels were moved into Martin Tower and housed there until 1841, when it was referred to as the Jewel Tower. In 1671, Colonel Thomas Blood and his men tried unsuccessfully to steal the Crown Jewels from the Martin Tower.
The outer ward encompassing the castle was built under Edward I, when the south side of the Tower of London was extended on the land that had previously been submerged by the River Thames. The St Thomas's Tower was built in this wall between 1275 and 1279, which later came to be known as the Traitor’s gate, and replaced the Bloody Tower as the castle's water-gate. However, between 1348 and 1355, a second water-gate, Cradle Tower, was added east of St Thomas's Tower for the private use of the King.
From 1547 onwards, the Tower of London was only used as a royal residence when its political and historic symbolism was considered useful and Edward VI, Mary I, and even Elizabeth I, stayed briefly at the Tower before their coronations.
During the 16th and 17th centuries, the Tower of London was known as a grim and forbidding prison, and between 1540 and 1640, the peak of imprisonment at the Tower, at least 48 cases of the use of torture were recorded. Many important figures that fell from the grace, like Sir Walter Raleigh, Elizabeth Throckmorton, Lady Jane Grey, Elizabeth I, and Anne Boleyn were held within its walls during that period. After the execution of Lady Jane Grey on 12 February 1554, Queen Mary I imprisoned her sister Elizabeth, later Queen Elizabeth I, in the Tower under suspicion of causing rebellion as Sir Thomas Wyatt had led a revolt against Mary in the name of Elizabeth. However, despite its notorious reputation as a place of death, only seven people were executed within the castle on Tower Green, including the innocent Anne Boleyn, before the World Wars of the 20th century. Executions were usually carried out on Tower Hill rather than in the Tower of London itself, and 112 people were executed on the hill over 400 years.
However, during the World Wars, the London Tower was again used as a prison. While during World War I, eleven men were tried and shot by firing squad at the Tower for espionage, during World War II, the Tower was once again used to hold prisoners of war that included Rudolf Hess, the deputy of Adolf Hitler, the last state prisoner to be held at the castle. German spy Joseph Jakobs shot dead on 15 August 1941, is the last person executed at the Tower.
During World War I, a bomb fell on the Tower of London and harmlessly landed in the moat. However, on 23 September 1940, during the Blitz of World War II, explosive bombs heavily damaged the castle, destroying several buildings and narrowly missing the White Tower. Today, protected as a World Heritage Site, the Tower of London is considered one of the country's most popular tourist attractions.