The authors give a brief history of the use of underground space in London and give details of the development and construction of the amenities provided for public transport, communications, water supply, sewers and deep level air raid shelters. There is a brief description of the geology of the area and of the methods of construction used initially and the way in which they have changed and developed. Construction materials and plant are also covered. There is a description of the growth of the unplanned system and of the difficulties that arise in the planning and construction of new amenities.
The first road tunnel under the River Thames was commenced in 1825 and opened to vehicles in 1843. It was purchased by the East London Railway Company in 1866 and opened to rail traffic in 1869. Today it forms part of the London Transport Underground Railway System (Fig. 1). The tunnel was constructed using a rectangular shield and was lined with brick. Apart from the approaches it is still in its original form today. Much of London's main line railway system developed in the nineteenth century, the first line being opened in 1836. The railways were built by independent companies between which there was intense competition and, at that time, little official control over their activities. In consequence, the cheapest practicable alignment was always sought, within the constraints imposed by the topography and the requirements of landowners. In consequence, few British Rail tunnels were built in London. Most of the tunnels, the majority of which were opened between 1837 and 1900, were necessitated by the presence of high ground, though in two cases the requirements to construct them was imposed upon the railway companies. In the first case, the Primrose Hill tunnel in the Hampstead area (opened 1837) was required by the landowners in order to preserve the future amenity of the district; the alternative would probably have involved extensive cuttings. In the second instance, involving the proposed line to Marylebone station, the Parliamentary Bill was at first rejected on the grounds of damage to property, but was later accepted provided that the immediate approach to the station was made in a tunnel approximately 2 km in length (opened 1899). The main line railways radiated from London and had their termini around the boundaries of the City. A Royal Commission of 1846 dismissed the idea of a central station for London. Passenger traffic across the central area grew until it strained the capacity of horse-drawn road vehicles and urban underground railways were therefore constructed, the first being opened in 1863. Between 1863 and 1890 many lines were constructed using the cut and cover method which, of course, caused considerable interference with roads and substantial demolition of property. In those days steam traction was used and ventilation was provided by constructing the lines with short lengths in open cutting between the cut and cover sections.