London Heathrow Airport to London St Pancras International (STP) train with Tfl Rail

Tfl Rail is a railway service operated by Transport for London in the United Kingdom. It operates on the Great Western Main Line and the Heathrow branch of the London Underground. The service runs from Paddington in London to Reading, Maidenhead, Slough, and Heathrow Airport. It also serves the towns of Taplow, Burnham, Twyford, and Hayes & Harlington. All trains are air-conditioned and feature onboard Wi-Fi, power sockets, and digital information screens. Tfl Rail offers a range of ticket types, including single and return tickets, season tickets, and Oyster cards. Oyster cards are the most popular ticket type, allowing passengers to pay for their journey with a single card. The most popular routes for Tfl Rail are Paddington to Reading, Paddington to Maidenhead, and Paddington to Heathrow Airport. These routes offer frequent services and provide passengers with a convenient way to travel between London and the surrounding areas.

The Heathrow Express is a train service from the United Kingdom that operates between London Heathrow Airport and Paddington Station in London. It runs every 15 minutes from 5:10am to 11:25pm, with a journey time of just 15 minutes. The train service offers two types of trains: the Express Class and the Business First Class. Express Class offers comfortable seating, free Wi-Fi, and power sockets, while Business First Class offers extra legroom, complimentary newspapers, and complimentary refreshments. There are three types of tickets available: Single, Return, and Group. Onboard facilities include a café bar, luggage storage, and a quiet zone. The most popular routes for the Heathrow Express are London Heathrow Airport to Paddington Station, and Paddington Station to London Heathrow Airport.

The "Tube" refers to the London Underground, a rapid transit system serving Greater London and parts of the adjacent home counties. It is operated by London Underground Limited (LUL), a wholly-owned subsidiary of Transport for London (TfL). Opened in 1863, it was the world's first underground passenger railway. The network, nicknamed "the Tube" due to its circular, deep-level tunnels, has 11 lines and 270 stations, covering approximately 250 miles. It carries over a billion passengers annually and is known for its iconic roundel symbol and schematic map.