In August we're going to be driving back from Charente-Maritime to Calais. We're planning to break the journey overnight somewhere near Calais and take it quite slowly, so are looking for something to do for a few hours somewhere roughly between Rouen and Calais. It can't be a big / time-consuming kind of attraction, like fighting into the centre of Rouen, but it needs to be something interesting enough that we can all look forward to it on what will otherwise be a pretty grim slog home.
Kids will be 8 and 5 and like wildlife / nature kind of things, swimming pools, playgrounds (obv), and have some tolerance of historic / museum kind of things. We like museums / historic kind of things and don't mind the others, although playgrounds can be pretty boring!
Does anyone happen to know of an excellent swimming pool complex / treetops walk / adventure playground / museum or similar in that kind of area?
Having trouble googling because the search area is so big.