Brunel's tunnel entrance to reopen this weekend

The Brunel Museum held two days of walking tours of the tunnel to give people a look at the 19th century engineering feat, which was Isambard Kingdom Brunel's first project.

The museum's director Robert Hulse said the tours sold out with 2,500 people taking part.

Robert said the tunnel which was built by Marc Brunel, who appointed his son Isambard as engineer, was a wonder of the age.

He said: "It was the oldest tunnel in the London Underground. It was the first tunnel anywhere under a river and it was the birthplace of the Tube, not just in London, but anywhere.

"For the non-specialist visitor it was the first underwater shopping arcade, a festival and fun fare.

"There were people dancing to minstrel music, there were tightrope walkers, music from steam organs and a troop of performing horses. It was like a 19th century rave."

The tunnel was originally meant to take cargo under the river between Wapping and Rotherhithe but, as no-one could afford the ramps for wheeled vehicles, it was eventually used to host festivals.

Back in the 1840s there were 50,000 visits in its first day of operation and by the end of the 15th week that figure had reached more than one million.

Robert said: "In 1843 that was half the population of London and they came down here to party."

This time round, the sell-out tours saw many turned away disappointed, and Robert plans to ask Transport for London and Mayor Boris Johnson for another weekend.

Since 1865 it has been used as a railway line, eventually becoming the East London line.

This closed in 2007 when work for the extension began, but is due to reopen in April this year making further walking tours impossible.

However, the museum will still have access to an entrance hall where there is a large amphitheatre.

Visits to the hall will take place this weekend (March 20 and 21) and more are planned for April 10.

"When people descend this weekend they will be the first people in 145 years to go into this amazing space," said Robert.

"At the moment we want to show it off and let people tell us what they think should be here.

"We may have lost the tunnel to the trains but we keep the entrance hall."

Go to brunel-museum.org.uk for more information.

HOW THEY DID IT?

Marc Brunel built a revolutionary 'shield', the height of three men and weighing 80 tonnes.

As the shield progressed through the clay under the Thames, workers lined it with rings of bricks.

The boring technique was copied throughout the world, including recent engineering such as the Channel Tunnel from Dover to Calais.

Brunel, who employed his son Isambard Kingdom as resident engineer on the project, thought it would take three years to build the Thames Tunnel.

However, it ended up taking 18 years as there were financial problems and leakages which caused collapses - the worst of which happened in 1828 when six workmen died.

Isambard was caught in that flood and was found close to death. However, he survived to have distinguished career.

*source - London and Docklands Historical Reader And Picture Collection, written by University of East London professor of civil engineering Professor Shafik Naib.