Hidden under the streets of red buses and black cabs, London is home to one of the world’s oldest transport systems. The London Underground, otherwise known by its nickname the Tube, is a staple of city life and handles up to five million passenger journeys a day.

But how exactly did it come to be? BBC Bitesize delves into the history of the world’s oldest underground railway.

The London Underground sign
Image caption,
The London Underground has been part of the city's history for over 160 years

1. Why was the London Underground invented?

The idea of an underground transport system was first proposed in 1843 by a City solicitor called Charles Pearson. The concept was part of a city improvement plan and formed an effort to reduce street traffic at a time where congestion in London had reached crisis point.

While his idea was initially rejected by Parliament, Pearson’s proposal aligned with an approved project from a separate group of entrepreneurs. As a result, the two parties came together and established the Metropolitan Railway Company in 1854.

2. When was the London Underground built?

Construction on the London Underground began in 1860 and the line was built just below street level using cut-and-cover technique. For the most part this required digging a trench approximately 10m (32 ft) wide and six metres (19ft) deep. Brick was then used to form walls and an arch around the cutting. Finally, two meters of top soil was laid upon the brick arch and the road above was built.

The route ran beneath existing main roads and as a result it was expensive and caused huge disruption in the streets. But after nearly two years of construction, the world’s first underground railway was open for business in January 1863. The first Tube line was the Metropolitan Railway which operated 3.75 miles (6km) and served seven stations between Farringdon and Paddington. It was an immediate commercial success.

An underground tube station
Image caption,
The first safe escalator on the Underground was installed at Earl's Court in 1911

3. What order were the Tube lines built in?

Much of the central London network was developed privately within the first 50 years of the Metropolitan line’s construction. The first stretch of the Metropolitan District Railway, from South Kensington to Westminster - now part of the District and Circle lines - opened in 1868 and the Circle line was completed in 1884.

It wasn’t until December 1890 that The City and South London Railway opened the world’s first deep-level electric railway. By the end of 1905, the Circle and District Lines switched from steam power to electric. However, it wasn’t until 1961 that the last steam locomotive passenger trains were replaced.

The latter half of the 20th Century saw the official opening of the Victoria line (1969) and the Jubilee line (1979).

On May 2022, the Elizabeth line was introduced to the network to celebrate the Platinum Jubilee year of Queen Elizabeth II. But despite travelling underground for the central part of the journey, it isn’t considered a new Tube line as it uses different rail infrastructure and much bigger trains.

Today there are 11 Tube lines, serving 272 station and covering 249 miles (402km).

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A map of the London Underground
Image caption,
It is thought that Harry Beck was paid five guineas for the Tube map's original design. That's the equivalent of £5.25!

4. Who designed the London Underground map?

The London Underground map was created in 1933 by technical draughtsman Harry Beck. The design was initially rejected by the Transport for London for being too radical, but is now an instantly recognisable symbol of the capital.

The map is noted for its simplicity and colourful criss-crossing lines, opposed to other maps of the time which emphasised distance and geographical accuracy.

In February 2024, Transport for London announced that the London map would undergo a significant change with the introduction of six new Overground lines.

Each new service will be marked by a different colour. They will be the Lioness line, the Mildmay line, the Windrush line, the Weaver line, the Suffragette line and the Liberty line.

A 'way out' sign
Image caption,
In 2007, the Tube carried one billion passengers in a year for the first time

5. What is the difference between the London Underground and Overground? And what is DLR?

As the name suggests, the London Underground mostly travels underground. It is operated entirely by Transport for London.

The London Overground is a rail network that serves London’s boroughs, as well as Watford in Hertfordshire. It runs above ground and while it is under the concession control and branding of Transport for London, it is franchised and forms part of the UK’s National Rail network.

The Docklands Light Railway, known as DLR, is a railway which first opened in 1987. It is unique among London transport links because it is a driverless train. It has operated under franchise by the private sector since 1997.

This article was published in April 2024

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