Eurostar is a high-speed railway service connecting London with Paris and Brussels. All its trains traverse the Channel Tunnel between England and France, owned and operated separately by Eurotunnel.

The London terminal is St Pancras International, with calling points at Ebbsfleet International and Ashford International in Kent. Calling points in France are Calais-Fréthun and Lille-Europe, with the main Paris terminus at Gare du Nord. Trains to Belgium terminate at Midi/Zuid station in Brussels. In addition, there are limited services from London to Disneyland Paris at Marne-la-Vallée – Chessy, and to seasonal destinations in southern France.

The service is operated by eighteen-coach Class 373/1 trains which run at up to 300 kilometres per hour (186 mph) on a network of high-speed lines. The LGV Nord line in France opened before Eurostar services began in 1994, and newer lines enabling faster journeys were added later—HSL 1 in Belgium and High Speed 1 in southern England. The French and Belgian parts of the network are shared with Paris–Brussels Thalys services and also with TGV trains. In the United Kingdom the two-stage Channel Tunnel Rail Link project was completed on 14 November 2007 and renamed High Speed 1, when the London terminus of Eurostar transferred from Waterloo International to St Pancras International.