The Elizabeth line is a high-frequency hybrid urban–suburban rail service in London and its suburbs. It runs services on dedicated infrastructure in central London from the Great Western Main Line west of Paddington to Abbey Wood and via Whitechapel to the Great Eastern Main Line near Stratford; along the Great Western Main Line from London Paddington to Reading and Heathrow Airport in the west; and along the Great Eastern Main Line between Stratford and Shenfield in the east. The service is named after Queen Elizabeth II, who officially opened the line on 17 May 2022 during her Platinum Jubilee year; passenger services started on 24 May 2022. Under the project name of Crossrail, the system was approved in 2007, and construction began in 2009. Originally planned to open in 2018, the project was repeatedly delayed, including for several months as a result of the COVID-19 pandemic. In May 2015, existing commuter services on a section of one of the eastern branches, between Liverpool Street and Shenfield, were transferred to TfL Rail; this precursor service also took control of Heathrow Connect in May 2018, and some local services on the Paddington to Reading line in December 2019. These services were augmented by a new central section in May 2022, and rebranded as the Elizabeth line. The outer services were connected to the central section in November 2022. By May 2023, the central section will have up to 24 nine-carriage Class 345 trains per hour in each direction.
