Attempts were made to decongest the city of London and solve the housing crisis. So, the British government built houses for working classes. All these efforts expanded the city and people found it difficult to walk to their work places. This made the underground rail transport essential for London.
Disadvantages: The development of the underground railways was criticized because.
(i) The underground railways were considered a menace to health due to the jack of oxygen created in the compartments by smoking pipes, fumes of gas lamps and coal dust.
(ii) A large number of houses for poor were displaced for its construction.
(iii) It added to the mess and unhealthy environment of the city.
(iv) People were afraid to travel underground.
(v) Many felt that 'iron monsters' added to the mass and unhealthiness of the city.