Crossrail is a 118-kilometre (73-mile) railway line under development in England, running through parts of London and the home counties of Berkshire, Buckinghamshire and Essex. The central section and a large portion of the line, between Paddington in central London and Abbey Wood in the south-east, are due to open in December 2018, when it will be named the Elizabeth line in honour of Queen Elizabeth II.
Part of the eastern section, between Liverpool Street and Shenfield in Essex, was transferred to a precursor service called TfL Rail in 2015; this section will be connected to the core route through central London to Paddington from May 2019. The western section, from Paddington to Heathrow Airport and Reading in Berkshire, is due to open in December 2019, completing the new east–west route across London and providing a new high-frequency commuter and suburban passenger service.
The project was approved in 2007 and construction began in 2009 on the central section and connections to existing lines that will become part of the route. It is Europe's largest infrastructure construction project. Its main feature is 21 km (13 mi) of new twin tunnels below central London.
These tunnels will run from Paddington to Stratford and Canary Wharf in the east. An almost entirely new line will branch from the main line at Whitechapel to Canary Wharf, crossing under the River Thames, with a new station at Woolwich and finally connecting with the North Kent Line at the Abbey Wood terminus.
Crossrail will be operated by MTR Corporation (Crossrail) Ltd as a London Rail concession of Transport for London, in a similar manner to London Overground. It is expected to relieve pressure on existing east-west London Underground lines such as the Central and District lines, as well as the Jubilee line extension and the Heathrow branch of the Piccadilly line. The need for extra capacity along this corridor is such that the former head of TfL, Sir Peter Hendy, predicted that the Crossrail lines will be "immediately full" as soon as they open. New nine-carriage Class 345 trains will run at frequencies in the central section of up to 24 trains per hour in each direction