Transportation from London Heathrow International : Heathrow is 15 miles west of central London. (Hotel Shuttles: Dot2Dot  departs from each of the terminals; while HotelHoppa buses serve the hotels in the Heathrow area.) 

NOTE:  1. According to research the Heathrow Express trains are not only three times faster than taxis, but also by a quarter cheaper. 
2. Berkshire residents
now have a 24-hr bus route service covering routes 75 & 78 into Heathrow Airport's central trmnal area (including London underground services & Heathrow Express, to Slough & Windsor & Maienhead, respectifvely.

The Heathrow Express from all Terminals to London : (All figures are estimates; transfer time does not include time needed to pick up a bag, or if you did not book your flights on one ticket, and your airlines either don't belong to the same Alliance, or do not have a code-share agreement.)
    From T2 to:  (a) T3 - walk 10-15-mins;  (b) from T4 or T5  via Heathrow Express, 20 mins - or take the London Underground; 16 mins.
    From T3:  (a) to T1 - a 10-min. walk;  (b) to T4 or T5  Heathrow Express -20 mins; or take the London Underground - 16 mins.
    From T4:  (a) to T1 or T3 take  Heathrow Express - 20 mins;  (b) to T5, take Bus 490 or 482 -20 mins. (T4 passengers should change  to the free transfer train to T1, 2 & 3).
    From T5:  (a) to T1 or T3 take Heathrow Express to London Paddington -20 mins; or London Underground - 16 mins.  (b) to T4 take bus 490 or 482 -  20 mins.

By Train:  (For Heathrow Train & Underground maps open: http://www.heathrowairport.com/transport-and-directions/trains).
   The Heathrow Express train offers non-stops to London's Paddington station, leaving every 15 minutes from either the 'Heathrow Terminal 5' station or the 'Heathrow Central' station (T3). The trip takes 15 minutes.  For more information open:  https://www.heathrowexpress.com/timetable-schedule/london-heathrow
   The Heathrow Connect to Paddington -stopping at  five National Rail stations en route, stops at Heathrow Central station (T1 T2 & T3)  - leaves every 30 minutes and takes 26 minutes; with a few minutes more for T4 or T5.
   By subway to central London: The London Underground Piccadilly line has a station for Terminals 2 & 3, and one station each at T4 & T5; has four stations serving  all terminals;  The average time to get from T2 & T3 tube stations to Central London is 40-50 minutes; for T4 & 5 under an hour. For more information visit www.tfl.gov.uk/fares-and-payments/ticket-types.

By Bus:
The Central Bus Station is between Terminals 2 & 3, reached within a few minutes (follow signs); it is open 24/7, while the trael center is open 6am-10:30pm. Bagage trolleys are available & an elevator takes you to the ground level . For more bus information open: www.tfl.gov.uk/maps/bus)
Buses connecting to Rail Stations: 
  (a) Two RailAir coach lines serve nearby railway stations serving different areas- one at Reading and one at Woking; and
  (b) London Buses to the Feltham station are served by route 285 departing from T2 & T3 and route 490 from T4 & T5.
Other Bus Services:  For West London bus service open: www.tfl.gov.uk  (for route mapss open:  www.tflgov.uk/maps/bus)
Express Buses: The Green Line route 724 serves Watford, St. Albans & Harlow; London Buses route X26 serves Croydon and Carousel Buses serve High Wycombe.
    London City Buses, First Berkshire and The Thames Valley serve nearby towns & suburbs.
    Night bus N9 serves central London during non-operatonal hours of trains.

Transfers to  London Gatwick or Stansted Airports: 
    To London Gatwick AP:  The National Express coach service offers direct link with up to 6 hourly departures - taking 75 mins. Get tickets at its desk in the Arrivals Halls of the terminals, or onboard the bus.  For more info call 087 781 8181 or visit nationalexpress.com
    To London Stansted AP:  The National Express coach service departs every 30-60 mins and takes 90 mins.  For more info use the same as to Gatwick).

NEWS:   Heathrow is planning for increased connectivity via rail links, allowing over 70 percent of UK's population to reach the Airport within 3 hours by public transit & 12M within one hour. Rail capacity is to increase three-fold to 15,000 seats per hour or from 18 to 40 trains per hour.

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