Thames Tunnel, Rotherhithe to Wapping

The plaque at Rotherhithe station.

London is a city layered with history, and some of the most fascinating stories lie beneath its surface. One such story belongs to the Thames Tunnel, an engineering marvel that was the first tunnel ever successfully built beneath a navigable river and a project so ambitious it took nearly two decades to complete.

Today, you might speed through it on the London Overground, barely giving a second thought to the brick arches passing by your window. But, in the 19th century, this passageway connecting Rotherhithe and Wapping was the scene of drama, innovation, and, for a short time, one of the city's most popular tourist attractions.

By the early 1800s, London's docks were booming, but the River Thames created a huge bottleneck. Building a new bridge downstream of London Bridge would have blocked the passage of tall-masted sailing ships. The only solution was to go under the river.

Several attempts to tunnel beneath the Thames had failed disastrously. The soft, treacherous ground beneath the riverbed made traditional mining techniques impossible. Enter the brilliant French-born engineer, Marc Isambard Brunel.

Brunel’s genius lay in his invention of the tunnelling shield. The idea, allegedly inspired by watching a shipworm bore through wood, was a revolutionary concept in civil engineering.

Keilyn at the bottom of the tunnel shaft. Notice the soot mark, from steam trains, still on the wall.

Patented in 1818, the shield was essentially a massive, rectangular, cast-iron frame divided into 36 compartments. Miners would work inside these individual cells, digging away a small section of earth in front of them while the surrounding frame held the unstable ground in place. Once a small segment was dug, the shield would be moved forward, and bricklayers would immediately line the new section of the tunnel behind it. This method was the key to conquering the soft, wet subsoil.

Work began in 1825, but the project was far from smooth sailing. It was a harrowing 18-year ordeal, plagued by financial crises, poor air quality, and most terrifyingly, repeated floods as the river burst through the thin crust of ground above.

The Hobbayne, Hanwell

Lily Pads.

Having already walked through Brent Lodge Park, I followed the Capital Ring, along the River Brent, and passed beneath the Wharncliffe Viaduct. This incredible piece of engineering must have looked incredible, when it was first completed, but now, with the tree cover, it is hard to see its full beauty.

This monolith of engineering skill was designed by Isambard Kingdom Brunel and his father, Marc. It was built using arches formed by hollow piers of engineering brick. It stands at an elevation of 20 metres (65.6 feet).

Wharncliffe Viaduct.

It opened in 1837 and is named after Lord Wharncliffe, who was the man that took the Great Western Railway Bill through Parliament. It is now Grade I listed.

The River Brent, flowing beneath this architectural marvel, is home to water voles, kingfishers and herons, amongst many others.

Brunel Museum

The Mural on the side of the Grand Entrance Hall.

The Brunel Museum is located within the Brunel Engine House building, Rotherhithe. This small but very informative museum allows you to descend into the Rotherhithe Thames Tunnel Shaft and visit the Engine House, where you will learn exactly what went in to building the world's first tunnel beneath a navigational waterway.

Marc Isambard Brunel designed Engine House as part of the Thames Tunnel project. Steam-powered pumps, used to extract water from the tunnel, were originally housed here, although it was used as a boiler house, between 1825-43. 

A Priming Pump from 1929.

In 1961 the Brunel Engine House opened and offered visitors the chance to see the interior of the building, as well as the Rennie flat V steam engine.

In 1974 the Engine House and Chimney were Grade II Listed. 

Between 1975-79 restoration work to stop structural decay was undertaken and completed.

The Chimney and Engine House.

In 2006 the Brunel Engine House changed its name to the Brunel Museum allowing the museum to incorporate other projects by the Brunel's. A new mural was created on the side of the Tunnel Shaft and benches were created in the style of Brunel bridges, in the garden area.

The Royal Albert Bridge, Saltash, as a bench at the museum.

Refurbishments, in 2007, included the moving of the Rennie flat V steam engine to the Chatham Historic Dockyard, thus creating a larger exhibition space and improved toilet facilities, within the Engine House. 

Memorabilia for the Thames Tunnel.