High speed rail was invented in Japan in the 1960s with the starting of the first Shinkansen or Bullet Train service. These trains offer a quick and convenient connection between cities, especially those considered too close to fly but too far to drive. Usually cities which may be 400 to 600 km apart. In several routes, thanks to the location of the airports and the associated checkin and security requirements, the high speed trains are faster connection city centre to city centre.
After Japan, thanks to the distances between various cities and the small areas of the various country coupled with a seamless travel facility between countries, the high speed trains have picked up very well in Europe.

The CAF designed and built Oaris is one such train. The Oaris trains are a modular concept in all means. They can be ordered in 4,6 or 8 car configurations. Further, the interiors of the trains are fully customisable to cater for various seating and class configurations. The intermediate coaches of the train can be ordered with either two or four door configuration thus allowing options for seating. These trains can include cafeteria areas, of varying lengths, different aisles between the seats, different luggage modules based on the number of places on the train, a variable number of toilets and PRM areas, amongst others.
The modularity of the trains are further extended to options of the gauge. While ordering, companies can choose from gauges between 1,435 mm to 1,668 mm. These trains are also designed to operate at various voltages from 1.5 and 3 Kv DC to 15 and 25 KV AC traction. The Oaris trains can not only be ordered with various gauges, they also offer complete interoperability between tracks of different gauges, signalling systems and electric power.

The Oaris trains are Electrical Multiple Unit trains and each car of the train has a motor bogie and a trailer bogie. This distributed traction adds to reliability of the train. Each cab car in the train, one at each end is 26.78 m long while the intermediate cars are 24.78 m long. The complete train length can vary from 202 to 404 m. The total traction power for an 8 car train is 10,560 KW and these trains are capable of reaching a top speed of 350 Km/h.
Each train is provided with air conditioning, CCTV monitoring of the entire train for passenger safety, audio and visual information system for all passengers, PA and intercom system, video entertainment system and a multi-purpose area with a vending machine, wifi, bike rack etc.
CAF is a Spanish MNC which commenced operations as a wagon reapair company in 1892. It started manufacturing trams in 1897 followed by manufacture of wagons in 1917. The company manufactures various types of trains, including high speed trains, regional trains and commuter trains; trams and metros in addition to other associates railways systems.