Metropolitan railways are urban, electric transport systems with high capacity and a high frequency of service.
Metros are totally independent from other traffic, road or pedestrians. They are consequently designed in tunnel, viaducts or on surface level but with physical separation. Metropolitan railways are the optimal public transport mode for a high capacity line or network service.
Some systems run on rubber-tyres but are based on the same control-command principles as steel-wheel systems.
In different parts of the world metro systems are also known as the underground, subway or tube.
Developments and trends
The first underground line opened in London in 1890. Since then, some 116 conurbations in Europe, America, Asia and the Middle East and North Africa have joined the ranks of cities with their own metro system.
Despite the high investment costs required, the development potential of metro systems is still large since there will be some 560 cities with populations of over one million by 2015.
The major development of the last years is the development of driverless train operation. This allows not only for cheaper, but also safer and more reliable operation, and last but not least better customer service.
Already 30 driverless lines are in operation and it is expected that in future 75% of new lines will be designed as driverless. Existing lines will also be massively retrofitted to driverless operation on the occasion of periodic modernisation of rolling stock or signalling equipment.
This development is not only a technological challenge, but also requires a complete rethinking of service philosophy, company organisation and processes, as well as staff qualifications.
Metros in figures
In 2006, metro networks carried some 155 million passengers per day, or 34 times the average daily number of air passengers. This comparison clearly demonstrates the economic and social importance of developing, organising and operating a metro system.
Metro is the most efficient transport mode in terms of energy consumption and space occupancy. In order to transport 50,000 passengers per hour and direction, a metro needs a right-of-way measuring 9m in width, whereas a bus would require 35m, and cars 175m. One kEP (kg equivalent petrol) will allow a single person to travel more than 48km by metro or 38km by bus, but no more than 19km by car.
http://www.uitp.com/Public-Transport/metro/index.cfm