Netherlands/Belgium road trip

By all means stop in Tournai - the cathedral is fabulous and the city has a Roman gate. Also see the church of St.-Brice, a combination of Romanesque and Gothic architecture. There are other medieval "sites" (not much left by now but still cool to see): Across the street from St.-Brice is a row of 17th-century houses where the tomb of Childeric was found during the houses' construction. And the foundations of the first Carolingian church can be seen in stone outlines in a plaza (not sure what the plaza is called). You're also going right by the town of Ath between Tourpes and Brussels - if you have time, stop here. Ath has a castle which you might need reservations to tour. The town square was originally the outer bailey of the castle, and the 12th-century keep is still there. If you can get in, you can go to the top of the keep and see the whole town. Ronse (Renaix in French) is a bit off the path from Tourpes but I recommend it too. The church of St.-Hermes was consecrated in the 11th century and what's really cool is that next to it are the Romanesque foundations of the original church. The 11th-century crypt goes under these foundations.

My suggestion is that you take a day to travel between DEn Haag and Ghent and do so via N57 (the road that goes near the cost, over the structures of the Delta Project), then via the Westerscheldttunnel to Terneuzen. It is not only much more interesting but it also offer stunning views of the oceans with plenty of opportunities to stop for pictures and sightseeing the Delta area. Very worth the detour.

From the route you have plotted, the windmills of Kinderdijk are a quick detour near Dordrecht. You may as well pay a quick visit to Antwerp, since you're passing through. The late gothic cathedral here is vastly underrated. The Grote Markt here is also quite impressive. There's a statue in the middle of it of a guy throwing a severed hand into the river. How cool is that? And if you're into the art of Reubens at all, there's quite a bit to see. "it is based on several trappist breweries we want to visit. " You realize, of course, that you can't actually tour most of the breweries? Some of them have reception centers where they serve food and drink, but for the most part, you can't visit the brewery itself. "We are big medieval history buffs" Again, because you're driving by these places anyway, check out Tournai and Kortrijk.