Rail transport is a commonly used mode of long-distance transportation in India. Almost all rail operations in India are handled by a state-owned company, Indian Railways, under the federal Ministry of Railways. The rail network traverses the length and breadth of the country, covering a total length of . It is said to be the 4th largest railway network in the world, transporting over 6 billion passengers and over 350 million tonnes of freight annually. Its operations cover twenty-eight states and three union territories and also provide limited service to Nepal, Bangladesh and Pakistan.
Railways were introduced to India in 1853, and by the time of India's independence in 1947 they had grown to forty-two rail systems. In 1951 the systems were nationalised as one unit—Indian Railways—to form one of the largest networks in the world. Locomotives manufactured at several places in India are assigned codes identifying their gauge, kind of power and type of operation. Colour signal lights are used as signals, but in some remote areas of operation, the older semaphores and disc-based signalling are still in use. Accommodation classes range from general through first class AC. Trains have been classified according to speed and area of operation. Many trains are officially identified by a four-digit code, though many are commonly known by unique names. The ticketing system has been computerised to a large extent, and there are reserved as well as unreserved categories of tickets.
The total length of track used by Indian Railways is about while the total route length of the network is . About 28% of the route-kilometre and 40% of the total track kilometre is electrified. Track sections are rated for speeds ranging from 75 to 160 km/h (47 to 99 mph). Indian railways uses three gauges, the Broad gauge (wider than the standard gauge—4 ft 8½ in (1,435 mm)); the metre gauge; and the narrow gauge (narrower than the standard gauge).
Indian broad gauge——is the most widely used gauge in India with of track. In some regions with less traffic, the metre gauge——is common, although the Unigauge project is in progress to convert all tracks to broad gauge. Narrow gauge is present on a few routes, lying in hilly terrains and in some erstwhile private railways (on cost considerations), which are usually difficult to convert to broad gauge. Narrow gauge covers a total of . The Kalka-Shimla Railway, the Nilgiri Mountain Railway and the Darjeeling Himalayan Railway are two notable hill lines that use narrow gauge.
In most places sleepers (ties) used are made of prestressed concrete, or steel or cast iron posts, though teak sleepers are still in use on few older lines. The prestressed concrete sleeper which is in wide use today is based on RDSO Drawing No. RDSO=T-2496. Metal sleepers were also extensively used before the advent of concrete sleepers. Indian Railways divides the country into four zones on the basis of the range of track temperature. The greatest temperature variations occur in Rajasthan, where the difference may exceed 70 °C (158 °F).
Indian Railways use a specialised classification code for identifying its locomotives. The code is usually three or four letters, followed by a digit identifying the model (either assigned chronologically or encoding the power rating of the locomotive). This could be followed by other codes for minor variations in the base model.
The three (or four) letters are, from left to right, the gauge of tracks on which the locomotive operates, the type of power source or fuel for the locomotive, and the kind of operation the locomotive can be used for. The gauge is coded as 'W' for broad gauge, 'Y' for metre gauge, 'Z' for the 762 mm narrow gauge and 'N' for the 610 mm narrow gauge. The power source code is 'D' for diesel, 'A' for AC traction, 'C' for DC traction and 'CA' for dual traction (AC/DC). The operation letter is 'G' for freight-only operation, 'P' for passenger trains-only operation, 'M' for mixed operation (both passenger and freight) and 'S' for shunting operation. A number alongside it indicates the power rating of the engine. For example '4' would indicate a power rating of above 4,000 hp (2,980 kW) but below 5,000 hp (3,730 kW). A letter following the number is used to give an exact rating. For instance 'A' would be an additional ; 'B' and so on. For example, a WDM-3D is a broad-gauge, diesel-powered, mixed mode (suitable for both freight and passenger duties) and has a power rating of 3400 hp (2.5 MW).
The most common diesel engine used is the WDM-2, which entered production in 1962. This 2,600 hp (1.9 MW) locomotive was designed by Alco and manufactured by the Diesel Locomotive Works, Varanasi, and is used as a standard workhorse. It is being replaced by more modern engines, ranging in power up to 4,000 hp (3 MW).
There is a wide variety of electric locomotives used, ranging between 2,800 to 6,350 hp (2.1 to 4.7 MW). They also accommodate the different track voltages in use. Most electrified sections in the country use 25,000 volt AC, but railway lines around Mumbai use the older 1,500 V DC system. Thus, Mumbai and surrounding areas are the only places where one can find AC/DC dual locomotives of the WCAM and WCAG series. All other electric locomotives are pure AC ones from the WAP, WAG and WAM series. Some specialised electric multiple units on the Western Railway also use dual-power systems. There are also some very rare battery-powered locomotives, primarily used for shunting and yard work.
The only steam engines still in service in India operate on two heritage lines (Darjeeling and Ooty) and on the tourist train Palace on Wheels. Plans are afoot to re-convert the Neral-Matheran to steam.
Traction voltages are changed at two places close to Mumbai. Central Railway trains passing through Igatpuri switch from AC to DC using a neutral section that may be switched to either voltage while the locomotives are decoupled and swapped. Western Railway trains switch power on the fly, in a section between Virar (DC) and Vaitarna (AC), where the train continues with its own momentum for about 30 m through an unelectrified section of catenary called a dead zone. All electric engines and EMUs operating in this section are the necessary AC/DC dual system type (classified "WCAM" by Indian Railways).
Coloured signalling makes use of multi-coloured lighting and in many places is automatically controlled. There are three modes:
Multiple aspect signals, by providing several intermediate speed stages between 'clear' and 'on', allow high-speed trains sufficient time to brake safely if required. This becomes very important as train speeds rise. Without multiple-aspect signals, the stop signals have to be placed very far apart to allow sufficient braking distance and this reduces track utilisation. At the same time, slower trains can also be run closer together on track with multiple aspect signals.
Semaphores make use of a mechanical arm to indicate the line condition. Several subtypes are used:
|1A||The First class AC: This is the most expensive class, where the fares are on par with airlines. Bedding is included with the fare in IR. This air conditioned coach is present only on popular routes between metropolitan cities and can carry 18 passengers. The coaches are carpeted, have sleeping accommodation and have privacy features like personal coupes.|
|2A||AC-Two tier: Air conditioned coaches with sleeping berths, ample leg room, curtains and individual reading lamps. Berths are usually arranged in two tiers in bays of six, four across the width of the coach then the gangway then two berths longways, with curtains provided to give some privacy from those walking up and down. Bedding is included with the fare. A broad gauge coach can carry 48 passengers.|
|FC||First class: Same as 1AC, without the air conditioning. This class is not very common.|
|3A||AC three tier: Air conditioned coaches with sleeping berths. Berths are usually arranged as in 2AC but with three tiers across the width and two longways as before giving eight bays of eight. They are slightly less well appointed, usually no reading lights or curtained off gangways. Bedding is included with fare. It carries 64 passengers in broad gauge.|
|CC||AC chair car: An air-conditioned seater coach with a total of five seats in a row used for day travel between cities.|
|EC||Executive class chair car: An air-conditioned seater coach with a total of four seats in a row used for day travel between cities.|
|SL||Sleeper class: The sleeper class is the most common coach, and usually up to ten coaches could be attached. These are regular sleeping coaches with three berths vertically stacked. In broad gauge, it carries 72 passengers per coach.|
|2S||Seater class: same as AC Chair car, but without the air-conditioning.|
|G orUR||General or Unreserved: The cheapest accommodation, with seats made of pressed wood and are rarely cushioned. Although entry into the compartment is guaranteed, a sitting seat is not guaranteed. Tickets issued are valid on any train on the same route if boarded within 24 hours of buying the ticket. These coaches are usually very crowded.|
At the rear of the train is a special compartment known as the guard's cabin. It is fitted with a transceiver and is where the guard usually gives the all clear signal before the train departs. A standard passenger rake generally has four general compartments, two at the front and two behind, of which one is exclusively for ladies. The exact number varies according to the demand and the route. A luggage compartment can also exist at the front or the back. In some trains a separate mail compartment is present. In long-distance trains a pantry car is usually included in the centre.
For super-fast trains, the first digit is always '2', the second digit is the zone, the third is the division and only the last digit is the serial number within the division. Trains travelling in opposite directions along the same route are usually labelled with consecutive numbers. However, there is considerable variation in train numbers and some zones, such as Central Railway, has a less systematic method for numbering trains. Most express trains also have a unique name attached to them which are usually exotic and are taken from landmarks, famous people, rivers and so on. Some notable examples are:
|1||Rajdhani Expresses||These are all air-conditioned trains linking major cities to New Delhi. The Rajdhanis have the highest priority and are the fastest trains in India, travelling at about 140 km/h (87 mph). There are only a few stops on a Rajdhani route.|
|2||Shatabdi and Jan Shatabdi Expresses||The Shatabdi trains are AC intercity seater-type trains. Jan-Shatabdi trains are generally non-AC and thus cheaper.|
|3||Super-fast Expresses or Mail trains||These are trains that have an average speed greater than 55 km/h (34 mph). Tickets for these trains have an additional super-fast surcharge.|
|4||Express||These are the most common kind of trains in India. They have more stops than their super-fast counterparts, but they stop only at relatively important intermediate stations.|
|5||Passenger and Fast Passenger||These are slow trains that stop at every single station, and are the cheapest trains. The entire train consists of the General-type compartments.|
|6||Suburban trains||Trains that operate in urban areas, usually stop at all stations.|
India has some of the lowest train fares in the world, and passenger traffic is heavily subsidised by freight. Until the late 1980s, Indian Railway ticket reservations were done manually. In late 1987, the Railways started using a computerised ticketing system. The entire ticketing system went online in 1995 to provide up to date information on status and availability. Today the ticketing network is computerised to a large extent, with the exception of some remote places. Computerized tickets can be booked for any two points in the country. Tickets can also be booked through the internet and via mobile phones, though this method carries an additional surcharge.
Discounted tickets are available for senior citizens (above sixty years) and some other categories of passengers including the disabled, students, sportspersons, persons afflicted by serious diseases, or persons appearing for competitive examinations. One compartment of the lowest class of accommodation is earmarked for ladies in every passenger carrying train. Some berths or seats in sleeper class and second class are also earmarked for ladies. Season tickets permitting unlimited travel on specific sections or specific trains for a specific time period may also be available. Foreign tourists can buy an Indrail Pass, which is modelled on the lines of the Eurail Pass, permitting unlimited travel in India for a specific time period.
For long-distance travel, reservation of a berth can be done for comfortable travel up to two months prior to the date of intended travel. Details such as the name, age and concession (if eligible) are required and are recorded on the ticket. The ticket price usually includes the base fare which depends on the classification of the train (example: super-fast surcharge if the train is classified as a super-fast), the class in which one wishes to travel and the reservation charge for overnight journeys.
If a seat is not available, then the ticket is given a wait listed number; else the ticket is confirmed, and a berth number is printed on the ticket. A person receiving a wait listed ticket will have to wait until there are enough cancellations to enable him to move up the list and obtain a confirmed ticket. If his ticket is not confirmed on the day of departure, he may not board the train. Some of the tickets are assigned to the RAC or Reservation against Cancellation which is between the waiting list and the confirmed list. These allow the ticket holder to board the train and obtain an allotted seat decided by a ticket collector, after the ticket collector has ascertained that there is a vacant (absentee) seat.
Reserved Railway Tickets can be booked through the website of Indian Railway Catering and Tourism Corporation Limited, and also through mobile Phones and SMS. Tickets booked through this site are categorised in to iTickets and eTickets. iTickets are those, which are booked by a passenger and then printed and delivered to the passenger for carrying during journey. eTickets are those, which the passenger can print himself at his end and carry while travelling. For booking an eTicket, one needs one of the authorised valid Photo Identity Card. Cancellation of eTickets are also done online, without the requirement for the passenger to go to any counter. Non-reserved tickets are available for purchase on the platform at any time before departure. A non-reserved ticket holder may only board the general compartment class. All suburban networks issue non-reserved tickets valid for a limited time period. For frequent commuters, a season pass (monthly or quarterly) guarantees unlimited travel between two stops.
After the creation of East Pakistan (later Bangladesh), many trains that used to run between Assam and Bengal had to be rerouted through the Siliguri Corridor (Chicken's Neck). However as of 2005 there are no passenger links between India and Bangladesh. A metre gauge link exists between Mahisasan (Mohishashon) and Shahbazpur. Another link is between Radhikapur and Birol. These last two links are used occasionally for freight.
There are two links between India and Nepal: Raxaul Jn., Bihar–Sirsiya, Parsa and Jaynagar, Bihar–Khajuri, Dhanusa. The former is broad gauge, while the latter is narrow gauge. A move to link the Indian and Sri Lankan railways never materialised. A ferry service however connects the closest railheads between Indian and Sri Lanka.
The Bhilai Steel Plant has a BG railway network. The Tatas (a private concern) operate funicular railways at Bhira and at Bhivpuri Road (as well as the Kamshet–Shirawta Dam railway line which is not a public line). These are not common carriers, so the general public cannot travel using these. The Pipavav Rail Corporation holds a 33-year concession for building and operating a railway line from Pipavav to Surendranagar. The Kutch Railway Company, a joint venture of the Gujarat state government and private parties, is involved (along with the Kandla Port Trust and the Gujarat Adani Port) to build a Gandhidham–Palanpur railway line. These railway lines are principally used to carry freight and not for passenger traffic.
Although generally IR has decided the freight tariffs on these lines, recently (February 2005) there have been proposals to allow the operating companies freedom to set freight tariffs and generally run the lines without reference to IR.