Tickets for Eurostar’s direct train service from London to the Netherlands go on sale at 4pm today.
They cost from £35 one-way.
The inaugural service left London St Pancras this morning but commercial services don’t start until April 4.
The journey time is three hours to Rotterdam and three hours and 41 minutes to Amsterdam.
Eurostar said it will ‘transform the connection between these key destinations, providing travellers with a compelling, environmentally friendly alternative to the airlines’.
Chief executive Nicolas Petrovic added: “Today’s inaugural service heralds an exciting new chapter in the expansion of high speed rail, strengthening the trading and tourism links between the UK and mainland Europe.
“With just six weeks to go until the start of service we are looking forward to providing customers with a fast, comfortable connection from London to Amsterdam and transforming travel between these important capital cities.”
Eurostar will have two departures a day, at 8.31am and 5.31pm.