Recommended itinerary from Liege to Utrecht
 

We are a family of 4 (parents +2 teenagers - 12,16).
We arrive to and depart from Liege, Belgium but most of our trip will be in the Netherlands.
Looking for a calm and easy itinerary from Liege to Utrecht (where our B&B is located) on the day of arrival. We land very early in the morning.
I thought of visiting the Three Land Maze and Maastricht. I still doubt about the caves near Maastricht.
Since this is our first visit to the Netherlands, please advise on an itinerary passing through typical rural landscape. We do not wish to take the highway.
Any recommendation is welcome.

You're driving?

Maastricht, Nijmegen/Arnhem (maybe the Openluchtmuseum), via Wageningen, Rhenen to Utrecht.

menachem, yes, we have a car.
Why?

Without a really good map, and someone who can read it it is almost impossible to get from Liege to Utrecht avoiding the motorways.
If you have time before your trip I suggest you buy a map. Failing that get one as soon as you can and really look at it.

Which caves do you mean? If you spend time at the drielandenpunt and then in Maastricht you may be happy to hit the motorway to get to Utrecht at a reasonable time. It is nearly 2 hours on the motorway from Maastricht to Utrecht.
Where are you flying from?

You can buy a map at a petrol station btw. And you will see lots of scenery from the motorway as you cross all the big rivers. You can always drop off the motorway to visit somewhere like Zaltbommel, or divert via Tiel.

wouldn't a navigation app, or tomtom or such do that trick?

I assume the OP means the caves in the Pietersberg in Maastricht.

http://www.grottenmaastricht.nl/

I would still recommend a drive along the Rhine from Arnhem to Utrecht, past Wageningen, Rhenen etc. Especially the part from Rhenen - Grebbeberg to Utrecht via Driebergen, Zeist, De Bilt and Utrecht is scenic, with perhaps a visit to Castle Amerongen. You could also follow the Rhine to Wijk bij Duurstede (lovely small town) and then Utrecht via Houten

http://www.utrechtslandschap.nl/?RubriekID=2057

A gps device is not as good as a map. Even if you can program in to avoid motorways it may not take you the nicest route.
As I said, after spending time in Vaals and Maastricht the motorway may be the best option anyway.

Nothing scenic about that though.