The Tower Bridge is a combined bascule and suspension bridge in London which crosses the River Thames. It consists of two towers tied together at the upper level by means of two horizontal walkways, designed to withstand the horizontal forces exerted by the suspended sections of the bridge on the landward sides of the towers.
The vertical component of the forces in the suspended sections and the vertical reactions of the two walkways are carried by the two robust towers. A traditional fixed bridge could not be built because it would cut off access by tall-masted ships to the port facilities in the Pool of London, between London Bridge and the Tower of London.
The bridge connected Iron Gate, on the north bank of the river, with Horselydown Lane, on the south – now known as Tower Bridge Approach and Tower Bridge Road, respectively. Until the bridge was opened, the Tower Subway – 400 m to the west – was the shortest way to cross the river from Tower Hill to Tooley Street in Southwark.
Opened in 1870, Tower Subway was among the world’s earliest underground (‘tube’) railway, but closed after just three months and was re-opened as a pedestrian foot tunnel.
The bridge is the subject of the popular nursery rhyme “London Bridge Is Falling Down” and is regularly featured in popular culture. The traditional ends of the medieval bridge were marked by St Magnus-the-Martyr on the northern bank and Southwark Cathedral on the southern shore.
Until Putney Bridge opened in 1729, London Bridge was the only road-crossing of the Thames downstream of Kingston-upon-Thames. On the relatively high, dry ground at the northern end of the bridge, a small, opportunistic trading and shipping settlement took root, and grew into the town of Londinium.
A smaller settlement developed at the southern end of the bridge, in the area now known as Southwark. The bridge was probably destroyed along with the town in the Boudican revolt (60 AD), but both were rebuilt and Londinium became the administrative and mercantile capital of Roman Britain.
The upstream fords and ferries remained in use but the bridge offered uninterrupted, mass movement of foot, horse, and wheeled traffic across the Thames, linking four major arterial road systems north of the Thames with four to the south.
Building work began in 1176, supervised by Peter, a priest and chaplain of St Mary Colechurch, which until its destruction in the Great Fire of London in 1666, stood in Conyhoop Lane, on the north side of the Poultry.
The costs would have been enormous, and Henry attempted to meet them with taxes on wool and sheepskins, but the project continued past his own lifetime. Hence it was that the traditional legend arose that London Bridge was built on wool packs, and a similar legend arose as to the foundations of Bideford Long Bridge in Devon, and perhaps many others.
It was finished by 1209 during the reign of King John. It had taken 33 years to complete, and John licensed out building plots on the bridge to help recoup the costs; but it was never enough.
Taking photographs of the Tower Bridge is a favorite London tourist activity, but you can also go inside the bridge, where you’ll have a magnificent view over London from the walkway between the two bridge towers.