After the expansion it will also be the first metro line in India to run under a river, which would cross the Hooghly river 32 metres below the water level. The term underground short now entered common usage of metro rail is a system of transportation fast mass type rail services for urban, thus characterized by a high frequency, and normally organized on the basis of fixed routes.
From the technical point of view the Metro is a rail, which is characterized by its own lane and traffic is regulated by systems of railway signaling and special circulation regimes. The subways can have underground paths as raised, as well as be traced normally at ground level, but they are usually characterized by the absence of road crossings and or pedestrian, and the use of electric traction.
The oldest underground network of Asia is one of Nagoya, in Japan, which was inaugurated by the company Meitetsu in 1895 though a regular urban services are only started in 1957, followed a year later by that of Tokyo. Other large cities with subway Japanese are the island of Okinawa.
Over the past thirty years, many cities in Korea have developed modern and extensive metropolitan networks. The largest is that of the South Korean capital Seoul (1974); others are in Pyongyang (1973) the capital of the Democratic Republic of Korea, Busan (1985), Daegu (1997), Incheon (1999), Gwangju (2004) and Daejeon (2006).
In China , after Beijing (1969), have built underground cities There are lines even in Hong Kong (1979) and Taipei (1996), the capital of Taiwan. Also in Asia have metro Manila (1984), Singapore (1987), Kuala Lumpur (1996) and Bangkok (1999).
In India's capital New Delhi is served by the metro only since 2002, while Calcutta saw the beginning of the service in 1984 and Chennai in 1997 in Mumbai, the most populous metropolis in India, the transformation of some suburban lines in underground has seen the opening of the network in 2004.
In Muslim countries there are often cars reserved for women only. Subways are on duty at Cairo , Ankara (1997), Tehran (1999), Izmir (2000), Bursa (2002), Dubai (2009) and Algiers (2011).