The Thalys train system seems to run Brussels, Cologne, Pars, Amsterdam, Rotterdam, and Antwerp. You can find many more destinations on the website of the company.
The Thalys train from Paris to Brussels will take on average around 1 hour 22 minutes. The train also serves beverages and sandwiches just in case you are hungry and need a drink.
Thalys direct = 2:07 hrs:min Thalys, IC change at Bruxelles Midi/Brussel Zuid = 2:15 Other itineraries = 3:00 or longer
It is recommended to arrive at least 30 minutes before departure for a Thalys train journey.
The departure times for the Thalys train from Brussels to Paris vary throughout the day. It is recommended to check the official Thalys website or contact their customer service for the most up-to-date information on departure times.
Take the Thalys to Amsterdam. When in Amsterdam, there will be a direct train to Groningen
by plane, train (Thalys) or car (about 8 hours)
catch an east midlands train to London st pancras, then catch a eurostar to brussels zuid (brussels south), then catch a thalys train to Amsterdam
You can take Eurostar from London St Pancras International to Paris Gare Du Nord and then Thalys to Amsterdam. Both trains are high-speed.
distance = 308 km, (highways 294 km), driving time 03H24, travel time by the Thalys train = 01H25.
If I travelled on a train, my mode of travel is by train.
In the United States, Amtrak is a great cross-country train travel system. This website, www.seat61.com/UnitedStates.htm, has deals on Amtrak fares.
Eurolines takes 4 hours. By car on a calm moment you can do it in 3 hours. You better take the high speed train Thalys, it is only 1h22.