The cost of a single train ticket between Amsterdam and Brussels is set to go up from €40.40 to €54 when the high-speed Fyra trains replace existing services, according to website treinreiziger.nl.
A flexible day return between the two cities will go up from €51.80 to €108 while a day return from Rotterdam to Antwerp will increase from €25 to €70, the website says.
The new prices were accidently published on the website of Belgian national railway company NMBS but have since been removed.
The introduction of high speed trains on the route from December 9 will cut journey times from three to two hours. However, travellers will have to book seats in advance and can no longer turn up to catch a train.
In addition, treinreiziger says there will be fewer services.
Early bookers will be able to get hefty discounts on the high-speed trains but, the website says, experience shows these are always sold out quickly. Passengers who want to avoid the higher fares will have to take alternative slower trains via Roosendaal.
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