What town would you recommend staying in? Would be coming by train from Paris.
stay in Bayeux...................
Assuming that your major interest is the D-Day sites, Bayeux is the best option. Most of the van-tours depart from Bayeux, you have the very good local WW II museum, the tapestry and the cathedral. For the purposes of visiting the attractive coastal towns to the east (like Honfleur) via public transportation, Caen works better.
No votes for Rouen and rent a car?
We are headed for our third time to Normandy this year - mainly for the D-Day sites and have stayed in Bayeux each time. Our second time we stopped in Rouen on our way there - it is about an 1.5 to Bayeux from there if I remember correctly, so not really convenient - especially if you are only going to be there three days. Head to Caen via the train and get a car rental there if you don't want to rent one in Paris. Bayeux is the most adorable town.
I liked Rouen a lot, but again, it was not my base for D-Day-related sites. it depends on where you want to go in Normandy. Base cities should not be selected at random. Make a list of the places you want to go and check driving times from Rouen on ViaMichelin.com.
Rouen is charming and makes a great day trip from Paris. It is not handy to the beaches,
If you have the time an auto tour of the region would be rewarding. But you asked for the name of a single town.
Definitely another vote for Bayeux as a base for the D-Day beaches. My dad and I did Giverny/Rouen in a day then went to Jumiege/Honfleur the next day before coming into Bayeux that evening. We spent a a little over a day and a half doing the D-Day beaches (we went down to Utah) before driving onto Mont St Michel. That’s an intinerary you could think about doing/modifying if you’re interested in seeing Rouen too.
But I would only consider Bayeux/Arromanches for your D-Day base or possibly Caen. Bayeux has some really wonderful stuff to see between the tapestry and the cathedral too. We rented a car out of CDG but you could rent out of Rouen or Caen since your going out by train.