Reims Champagne is a base for impressively fast fighters, but they accept GA aircraft. Worth adding to your log book, and to spend a half hour watching the fighters at work. As far as I remember they do not have Avgas available.
Reims Prunay is a small airfield with a maintenance base and Avgas.
Both are within reasonable distance of the town. Reims is a good sized town with many hotels and restaurants serving good food and reasonably prices champers, and has a big cathedral with some connection to Jonn of Arc.
Laon is a very small town with a beautifully designed small cathedral, and was one of the main cities used by Charlemagne. The town itself would justify a couple of hours to visit.
If it is one or the other I wuold plump for Reims, and use Prunay, making sure you check customs hours and book ahead if necessary.