London's 1091 tornado - destroying a bridge, churches and 600 homes

London Bridge, as the well-known nursery rhyme attests, is prone to 'falling down'. Such an event indeed occurred on October 17th 1091, when the original wooden Bridge was one of the victims of the first documented tornado in British history.

The London tornado struck the heart of the city, causing a great deal of damage. The church of St Mary-le-Bow was completely levelled, to the extent that four huge 26-foot rafters were driven so far into the earth that only four feet remained visible above ground. Many more buildings, including around 600 mainly wooden houses, were also demolished, although amazingly, only two deaths were recorded.

According to William of Malmesbury, the foremost English historian of the 12th century, 'Churches and houses, enclosures and walls were left in heaps. Huge timbers, as long as five men, were ripped from the roof of St Mary and lodged into the ground to a depth of six metres.' John or Florence of Worcester chronicled “a violent whirlwind… shuck and demolished more than six hundred houses and a great number of churches in London.'

The wooden London Bridge, only recently built in the reign of William the Conqueror, was completely demolished. After the tornado William Rufus rebuilt the bridge, but this too was short-lived, as a fire destroyed it only 40 years later. After this, the bridge was rebuilt in more enduring stone.

From accounts of the damage, modern meteorologists estimate that the tornado would have rated T8 on the tornado scale, which runs from T1 to T10. If so, winds of up to 240 mph would likely have struck the city.

The London Tornado of 1091 still goes down in history as the worst event of its kind inflicted on London.