The Bascule Chambers

What are the Bascule Chambers?

The Bascule Chambers sits below Tower Bridge’s two Towers and allow for the movement of the Bridge’s huge 400-ton counterweights, which swing down during Bridge Lifts.

How large are the Bascule Chambers?

• The Bascule Chambers are like two enormous halls, 27 metres high, inside the piers. Their width x length x height measurements are: 21 x 59 x 27 metres.
• Each of our mighty bascules weight over 1,200 tons. A 400-ton counterweight help them to descend into the Bascules Chambers.
• The walls in the piers are a minimum of 304.8 cm (10 foot) thick made of Staffordshire Brindle and Gault bricks, faced with Granite.

How were the Bascule Chambers built?

• The piers for the Bascule Chambers were built using 12 caissons, steel cages lowered into the Thames.
• A team of divers lead by a Quaker, Friend Samuel Penney, then worked inside the caissons excavating the foundations.
• The bascules were were built vertically to ensure river traffic could still pass. They were the final part of Tower Bridge’s construction.

Tower Bridge's Bascule Chambers are one of London’s greatest hidden spaces. These cavernous brick-lined, subterranean spaces are normally out of bounds for everyday visitors. 

On rare occasions the Bascule Chambers are opened up for our most popular Behind-the-Scenes tours. Led by one of our expert guides and a member of our Technical Team who keeps Tower Bridge running, you will discover the fascinating history of Tower Bridge and visit the behind-the-scenes operational areas.

Sign up to our newsletter to be the first to hear when tickets are on sale. 

In the past, Tower Bridge have worked closely with partners to create and host unique artistic events such as concerts and film screenings within the cathedral-like space of the Bascule Chambers. Each event has enthralled visitors and captured their imaginations.

For a taste of these previous events, watch a sample of a concert curated by composer Iain Chambers.