What is the check-in process like at the station?

Most European train services do not require check-in and are much the same as boarding a domestic train in the UK, in that you have to show your tickets to the conductor on the train. For international services you must always carry a valid passport.

Some stations do require that your bags are scanned prior to boarding the train, and you may be asked to show your tickets. You should allow enough time for this just in case.

The Eurostar requires a short airline-style baggage scan and passport control. You may be asked to pass your bags through an X-ray security check. You should leave at least a half hour prior to departure for this.