Has anyone ever visited Douai for the Festival of Giants held in July? I watched a PBS travel show that included the festival and it looked like a lot of fun. Is it possible to do a day trip from Paris to Douai?
Answering only your last question: Yes, a day trip is doable, it's only 1 to 1.5 hours station to station time, use this website to see the train schedules:Rail SchedulesThe exact date doesn't matter, select 0600 as the departure time so you'll get a look at the earliest trains as well as later ones. You don't use this website to buy tickets, you'll probably buy your tickets point to point a day or two before your trip.