In the first half of the 1800s, London's population grew at an astonishing rate, and the central area became increasingly congested. In addition, the expansion of the overground railway network resulted in more and more passengers arriving in the capital. However, in 1846, a Royal Commission decided that the railways should not be allowed to enter the City, the capital's historic and business centre. The result was that the overground railway stations formed a ring around the City. The area within consisted of poorly built, overcrowded slums and the streets were full of horse-drawn traffic. Crossing the City became a nightmare. It could take an hour and a half to travel 8 km by horse-drawn carriage or bus. Numerous schemes were proposed to resolve these problems, but few succeeded. 

19 世纪上半叶，伦敦人口以惊人的速度增长，中心地区变得越来越拥挤。此外，随着地面铁路网络的扩张，越来越多的乘客来到伦敦。然而，1846 年，皇家委员会决定不允许铁路进入首都的历史和商业中心--伦敦市。结果，地面火车站形成了一个环形包围圈。城内都是建筑简陋、拥挤不堪的贫民窟，街道上到处都是马车。穿越城市成了一场噩梦。乘坐马车或公共汽车行驶 8 公里需要一个半小时。为了解决这些问题，人们提出了许多方案，但几乎没有成功的。

Amongst the most vocal advocates for a solution to London's traffic problems was Charles Pearson, who worked as a solicitor for the City of London. He saw both social and economic advantages in building an underground railway that would link the overground railway stations together and clear London slums at the same time. His idea was to relocate the poor workers who lived in the inner-city slums to newly constructed suburbs, and to provide cheap rail travel for them to get to work. Pearson's ideas gained support amongst some businessmen and in 1851 he submitted a plan to Parliament. It was rejected, but coincided with a proposal from another group for an underground connecting line, which Parliament passed.

查尔斯-皮尔逊（Charles Pearson）是解决伦敦交通问题最积极的倡导者之一，他是伦敦市的一名律师。他认为修建地下铁路既能带来社会和经济效益，又能将地面火车站连接起来，同时还能清除伦敦的贫民窟。他的想法是将居住在市内贫民窟的贫困工人搬迁到新建的郊区，并为他们提供廉价的铁路出行服务。皮尔逊的想法得到了一些商人的支持，1851 年，他向议会提交了一份计划。该计划被否决，但与此同时，另一个团体提出了一条地下连接线的建议，议会通过了该建议。

The two groups merged and established the Metropolitan Railway Company in August 1854. The company's plan was to construct an underground railway line from the Great Western Railway's (GWR) station at Paddington to the edge of the City at Farringdon Street – a distance of almost 5 km. The organisation had difficulty in raising the funding for such a radical and expensive scheme, not least because of the critical articles printed by the press. Objectors argued that the tunnels would collapse under the weight of traffic overhead, buildings would be shaken and passengers would be poisoned by the emissions from the train engines. However, Pearson and his partners persisted. 

1854 年 8 月，两个集团合并成立了大都会铁路公司。该公司的计划是修建一条从帕丁顿大西部铁路（GWR）车站到法灵顿街城市边缘的地下铁路，全长约 5 公里。该组织在为这样一个激进而昂贵的计划筹集资金时遇到了困难，尤其是因为媒体刊登了一些批评文章。反对者认为，隧道会在车流的重压下坍塌，建筑物会受到震动，乘客会因火车引擎排放的废气而中毒。然而，皮尔逊和他的合伙人坚持了下来。

The GWR, aware that the new line would finally enable them to run trains into the heart of the City, invested almost £250,000 in the scheme. Eventually, over a five-year period, £1m was raised. The chosen route ran beneath existing main roads to minimise the expense of demolishing buildings. Originally scheduled to be completed in 21 months, the construction of the underground line took three years. It was built just below street level using a technique known as 'cut and cover'. A trench about ten metres wide and six metres deep was dug, and the sides temporarily held up with timber beams. Brick walls were then constructed, and finally a brick arch was added to create a tunnel. A two-metre-deep layer of soil was laid on top of the tunnel and the road above rebuilt. 

英国皇家西伯利亚铁路公司意识到，这条新线路最终将使他们能够将火车开进城市的中心地带，因此为该计划投资了近 25 万英镑。最终，在五年的时间里，共筹集到 100 万英镑。所选线路从现有主干道下方穿过，以尽量减少拆除建筑物的费用。地下线路原计划在 21 个月内完工，但建造过程耗时三年。地下线路采用一种被称为 “切割和覆盖 ”的技术，建造在街道平面之下。先挖出一条宽约十米、深约六米的壕沟，再用木梁临时支撑起壕沟两侧。然后砌上砖墙，最后再用砖拱起隧道。在隧道顶部铺上两米深的土层，然后重建上面的道路。

The Metropolitan line, which opened on 10 January 1863, was the world's first underground railway. On its first day, almost 40,000 passengers were carried between Paddington and Farringdon, the journey taking about 18 minutes. By the end of the Metropolitan's first year of operation, 9.5 million journeys had been made. 

大都会线于 1863 年 1 月 10 日开通，是世界上第一条地下铁路。开通首日，帕丁顿和法灵顿之间的客运量达到近 40,000 人次，全程耗时约 18 分钟。到大都会地铁运营第一年结束时，共运送了 950 万人次。

Even as the Metropolitan began operation, the first extensions to the line were being authorised; these were built over the next five years, reaching Moorgate in the east of London and Hammersmith in the west. The original plan was to pull the trains with steam locomotives, using firebricks in the boilers to provide steam, but these engines were never introduced. Instead, the line used specially designed locomotives that were fitted with water tanks in which steam could be condensed. However, smoke and fumes remained a problem, even though ventilation shafts were added to the tunnels. 

就在大都会线开始运营的同时，该线路的第一批延长线也获得了批准；这些延长线在接下来的五年中陆续建成，分别通往伦敦东部的摩尔盖特和西部的哈默史密斯。最初的计划是使用蒸汽机车牵引列车，利用锅炉中的耐火砖提供蒸汽，但这些机车从未投入使用。取而代之的是，该线路使用了专门设计的机车，机车上安装了水箱，可以在水箱中冷凝蒸汽。然而，尽管在隧道中加装了通风井，烟雾和烟尘仍然是个问题。

Despite the extension of the underground railway, by the 1880s, congestion on London's streets had become worse. The problem was partly that the existing underground lines formed a circuit around the centre of London and extended to the suburbs, but did not cross the capital's centre. The 'cut and cover' method of construction was not an option in this part of the capital. The only alternative was to tunnel deep underground. 

尽管地铁在不断延伸，但到了 19 世纪 80 年代，伦敦街道的拥堵情况却变得更加严重。问题的部分原因是现有的地下线路围绕伦敦市中心形成了一个环形，并延伸到郊区，但没有穿过市中心。在首都的这一地区，“切割和覆盖 ”的施工方法是不可行的。唯一的选择是在地下深处挖掘隧道。

Although the technology to create these tunnels existed, steam locomotives could not be used in such a confined space. It wasn't until the development of a reliable electric motor, and a means of transferring power from the generator to a moving train, that the world's first deep-level electric railway, the City & South London, became possible. The line opened in 1890, and ran from the City to Stockwell, south of the River Thames. The trains were made up of three carriages and driven by electric engines. The carriages were narrow and had tiny windows just below the roof because it was thought that passengers would not want to look out at the tunnel walls. The line was not without its problems, mainly caused by an unreliable power supply. Although the City & South London Railway was a great technical achievement, it did not make a profit. Then, in 1900, the Central London Railway, known as the 'Tuppenny Tube', began operation using new electric locomotives. It was very popular and soon afterwards new railways and extensions were added to the growing tube network. By 1907, the heart of today's Underground system was in place. 

虽然拥有建造这些隧道的技术，但蒸汽机车却无法在如此狭窄的空间内使用。直到开发出可靠的电机以及将动力从发电机传输到行驶中的列车的方法，世界上第一条深层电气化铁路--伦敦城市和南伦敦铁路才成为可能。该线路于 1890 年开通，从伦敦市一直通往泰晤士河以南的斯托克韦尔。列车由三节车厢组成，由电动引擎驱动。车厢很窄，车窗很小，仅在车顶下方，因为人们认为乘客不会愿意向外看隧道的墙壁。这条线路并非没有问题，主要原因是电力供应不稳定。虽然伦敦城市和南部铁路在技术上取得了巨大成就，但却没有盈利。1900 年，被称为 “Tuppenny Tube ”的伦敦中央铁路开始使用新型电力机车运营。这条铁路非常受欢迎，不久之后，又有新的铁路和支线加入到不断扩大的地铁网络中。到 1907 年，今天地铁系统的核心部分已经建成。