This is one of only four towers built in London using a top down construction method where the core and crown are built first and then the floors hung from the crown.
The then CGU Tower was the first building in the City of London to be taller than the height of St Paul's Cathedral.
Arguably the best example of high quality International architecture in London, this building is up to be listed by English Heritage.
It has had three name changes in five years. First it was CGNU and then Aviva and is now called St Helen's after the nearby church.