The London skyline was illuminated with a festival of light to mark the 'topping out' of the iconic tower at 30 St Mary Axe in the City of London. A 'topping out ' is the celebration of the finalising of the building's structure and is traditionally marked with a party by the construction company. At 6:00pm, a final steel beam was raised ceremonially through smoke to the top of the building followed by a dazzling fifteen-minute light and laser show. This dramatic display was visible across Londons skyline.