Why does Tower Bridge open?

Tower Bridge opens to let tall boats pass through, but have you ever wondered where those boats are going?

Today, most boats on this part of the Thames are tourist boats. That hasn’t always been the case though. When Tower Bridge was first built in 1894, ships sailing on the Thames were carrying other important types of cargoes.

Black and white image of vessels queuing to pass through Tower Bridge

Why was Tower Bridge designed to lift?

The part of the Thames where Tower Bridge sits is called the Pool of London, which in the Victorian era was the busiest port in the world.

Cargo ships came here from around the world, carrying goods such as cotton, sugar, and tea. These cargoes were offloaded into warehouses which lined the river banks between London Bridge and Limehouse, in East London.

When a new bridge was proposed next to the Tower of London, many people were concerned with how cargo ships would reach the warehouses on the other side of the new bridge.

Fortunately, their concerns were listened to. It was decided that the new bridge's design could not obstruct the sailing ships from accessing the upper Pool of London. Over 50 different designs were submitted with many unique solutions to the problem. The design that included opening roadways, or bascules, by Sir Horace Jones and Sir John Wolfe Barry, was deemed the best.

The Götheborg of Sweden by Edward Hasler

How often does Tower Bridge open?

On average, Tower Bridge opens its bascules around 800 times a year. That's around twice a day.

You would be forgiven for thinking that's a lot of Bridge Lifts. However, in 1894, Tower Bridge’s first year of operation, the bascules were lifted 6,194 times. An average of 17 times per day.

Back then, staff at Tower Bridge were on the lookout 24 hours a day for any vessels ready to pass through, and the bascules were opened as soon as the road was cleared.

This process changed on 1 January 1971. Now, ships must book a Bridge lift at least 24 hours in advance, and all requests must be submitted in writing.

Götheborg of Sweden crossing Tower Bridge in June 2022 ©Edward Hasler

Did you know?

The record for the greatest number of Bridge lifts in one day was in 1910, when it opened 64 times!

Le Boreal cruising through Tower Bridge

Do you have to pay to open Tower Bridge?

The cost for opening Tower Bridge has remained the same since 1894: it’s completely free.

River traffic has always had priority on this stretch of the Thames. It was a condition of its design that Tower Bridge did not obstruct river traffic coming into the Pool of London. This also meant that vessels could not be charged.

All Bridge Lifts are funded by City Bridge Foundation, historically known as Bridge House Estates. City Bridge Foundation is a 900-year-old organisation that funds the upkeep of five of bridges in Central London. These are Tower Bridge, London Bridge, Southwark Bridge, Blackfriars Bridge and Millennium Bridge.

Tower Bridge lifts for a sailing barge

Who can ask Tower Bridge to lift?

Any vessel that is more than 9m (30ft) tall, can request a bridge lift. 

The Bridge is bound by an Act of Parliament (the Tower Bridge Act of 1885) to give river traffic priority over road traffic. This means the Bridge can be asked to lift at any time of day or night!

Bridge Lift during sunset, taken from a vessel approaching Tower Bridge

When can I see Tower Bridge open?

Check our Bridge Lift timetable for more information about all our upcoming Bridge Lifts. 

Where is the best place to watch a Bridge Lift?

Watching Tower Bridge lift is a must-see on any trip to London. 

You can watch a Bridge Lift from any of the surrounding outside areas. If you are on the southwest side of the Bridge, you will also see the ships pass the iconic Tower of London. 

If you happen to be in the Tower Bridge Walkways when the Bridge lifts, you will be lucky enough to see the ships passing below your feet.