The shape of it
The loop went north first: Bamberg for a night, then Düsseldorf for two, then across the Dutch border to La Trappe, down to Antwerp, and a week in Belgium with Brussels as the pivot. Bruges got a night, Westvleteren a detour, Chimay a night in the woods at Poteaupré.
The return was the part nobody plans well: Chimay to Zwiefaltendorf is five and a half hours, and the reward is a village brewery with rooms above the brewhouse and a dinner of Swabian things that have no equivalent anywhere else on the route.
It was February, so the beer gardens were shut and the towns were empty. Bruges in the rain at eight in the morning, with nobody on the Markt, is a different city from the one in the photographs, and better.
What it taught about driving
Ten beds in seventeen days is too many. The Belgian week worked because Brussels held for two nights; the German legs did not, and Bamberg in particular deserved the second night it did not get.
The car made the Trappist day possible — La Trappe, Westvleteren and Chimay are not connected by any sensible train — but it also made the trip a sequence of car parks. The next version cut the driving and added rail where the beer was in a city.
Germany and Belgium both enforce their low-emission zones; a rental without the right sticker is a fine waiting to happen. Check the Umweltzone before booking the car, not after.