1 April

• 1871 – Brill Tramway opens between Quainton Road and Wooton.
• 1871 – Great Northern Railway opens branch from Alexandra Palace to Enfield.
• 1872 – Edgware, Highgate and London Railway extends from Finchley Central to High Barnet.
• 1966 – British Airports Authority begins operations and takes control of Heathrow, Gatwick and Stansted Airports.
• 1986 – Terminal 4 opens at Heathrow Airport.
• 1994 – Railtrack forms on the privatisation of British Rail.
• 1994 – Waterloo & City line becomes part of London Underground.

2 April

• 1937 – Battersea Park rail crash kills 10 when a signalling error causes a train to run into the rear of another at speed.

3 April

• There are no anniversaries today

4 April

• 1859 – London and South Western Railway opens line from Raynes Park Junction to Epsom.
• 1901 – The first electric trams in London are run by London United Tramways.
• 1910 – Great Northern Railway extends from Grange Park to Cuffley and closesEnfield station to passengers.

5 April

• 1952 – The last tram runs through Kingsway tramway subway.
• 1964 – Full-scale trials of automatic train operation begin between Woodford and Hainault on the Central line.
• 1968 – RAF pilot Alan Pollock flies a Hawker Hunter jet below the upper span of Tower Bridge as part of a protest that the 50th anniversary of the founding of the RAF was not celebrated.
• 1994 – London Underground operation of the Waterloo & City line begins.

6 April

• 1914 – Charing Cross, Euston and Hampstead Railway extends from Charing Cross to Embankment.

7 April

• 1979 – Last AEC Regent III RT bus ends its service.
• 1986 – District line starts regular daily service to Kensington {Olympia}.

8 April

• 1953 – Stratford tube crash kills 12 people when a train runs into another in tunnel between Stratford and Leyton.
• 1962 – First experiments in automatic train operation begin between Stamford Brook and Ravenscourt Park.
• 1968 – A fire on a BOAC passenger plane following an emergency landing kills 5. Stewardess Barbara Jane Harrison is posthumously awarded the George Cross for heroism.

9 April

• There are no anniversaries today

10 April

• 1865 – Third Hampton Court Bridge over the River Thames opens.

11 April

• There are no anniversaries today

12 April

• 1869 – District Railway extends from Gloucester Road to West Brompton.

13 April

• 1868 – Metropolitan Railway extends from Baker Street to Swiss Cottage.
• 1901 – Death of Sir Edward Watkin, railway executive.

14 April

• 1940 – Northern line extends from East Finchley to High Barnet.
• 1951 – Death of Sir Charles Bressey, road engineer.

15 April

• 1968 – Erected in 1963 to enable the construction of the Underground station concourse below the road junction, the Oxford Circus Umbrella road deck is removed.

16 April

• 1917 – Baker Street and Waterloo Railway extends from Willesden Junction to Watford Junction.

17 April

• There are no anniversaries today

18 April

• 1964 – High capacity Red Arrow commuter express bus service starts operating.

19 April

• There are no anniversaries today

20 April

• 1924 – City and South London Railway extends from Euston to Camden Town to connect to the Charing Cross, Euston and Hampstead Railway.
• 1984 – A bomb explodes in the baggage claim area of Heathrow Airport's Terminal 2 injuring 22.

21 April

• There are no anniversaries today

22 April

• There are no anniversaries today

23 April

• 1959 – London Heliport in Battersea opens.

24 April

• 1969 – BEA Airtours is formed by British European Airways as a low-cost subsidiary for package holiday flights.

25 April

• There are no anniversaries today

26 April

• 1868 – Two trains collide at the Metropolitan Railway's Swiss Cottage station (now closed) injuring three.
• 1870 – Great Eastern Railway opens branch from Lea Valley junction to Shern Hall Street, Walthamstow.
• 1926 – A gyratory system is introduced in Trafalgar Square so that all vehicles travel clockwise around the square.
• 1971 – The government announces that Foulness, Essex has been selected as the site of London's third airport over the Roskill Commission's recommendation for Cublington, Buckinghamshire.

27 April

• 1910 – Louis Paulhan takes off from Hendon on the first leg of his flight to win the 1910 London to Manchester air race.
• 2010 – East London Line opens as part of London Overground.

28 April

• 1923 – London North Eastern Railway opens Wembley Exhibition loop line and station.

29 April

• There are no anniversaries today

30 April

• There are no anniversaries today

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