The existing London Bridge, the most famous of all the Thames bridges, was designed by John Rennie, begun in 1825 by his sons John (afterwards Sir John) and George Rennie, and completed in 1831. It is borne by five semi-elliptical granite arches (that in the centre having a span of 152+ feet) and is 928 feet long. Its width, originally 54 feet, was increased to 63 feet in 1903-4. Its total cost, including the approaches and widening, was �2,556,000 (the bridge itself �815,000). On the south bank it debouches in the borough of Southwark, near Southwark Cathedral and London Bridge Station.
It seems probable that the Romans erected a bridge over the Thames at or near this point, where the river is narrower than either above or below. At least one wooden bridge was constructed by the Saxons. The first stone bridge was begun in 1176 by Peter of Colechurch, at the instance of Henry II., but it was not completed till 1209, in the reign of King John. It stood opposite the church of St. Magnus, about 60 yards below the present bridge. Rows of wooden houses sprang up on each side, and in the middle was a chapel dedicated to St. Thomas Becket (good view of the old bridge in Hogarth's 'Marriage a la Mode' series). At each end stood a fortified gate, on the spikes of which the heads of traitors were exposed. Though the buildings on the bridge (finally removed in 1758) were more than once burned down, the bridge itself remained until 1832, when it was removed after the completion of the present bridge. It was the only bridge over the Thames until 1739. The span of its arches ranged from 10 to 33 feet, and the total waterway was 337 feet (as compared with the 690 feet of to-day). The removal of the obstruction caused by the old bridge lowered the low-water level by 5 feet and deepened the river-bed considerably. An arch of this bridge was unearthed in 1921.
London Bridge divides the Thames into 'above' and 'below' bridge. Down-stream is the Port of London, the part immediately adjacent to the bridge being known as the Pool. Large sea-going vessels can still ascend to London Bridge, but the construction of the Tower Bridge has transferred the seat of the chief shipping activity to a point somewhat lower down. Above bridge the traffic consists mainly of barges and small steamers.
The View from the bridge is of great interest. Below bridge is the crowded waterway of the river itself, with the Tower Bridge, the white spire and cupola of St. Magnus (immediately to the left), Billingsgate Market, the Custom House, the Tower, and the Monument. Above bridge are Cannon Street Station, St. Paul's Cathedral, numerous City churches, St. Saviour's (close by, on the south bank), and Barclay & Perkins's Brewery.
It has been calculated that from 20,000 to 25,000 vehicles and about 120,000 foot-passengers cross London Bridge every day.
