One day trip to Normandy

A car will give you the flexibility to see and do what you want. Have an early breakfast, pick up your rent a car and boogie. It's been awhile so I'm not sure about the driving time but it's certainly reasonable for a day trip from Paris and the roads are excellent (and fast). Some people train into say Bayeux and pick up a car (although this does somewhat restrict you). Don't miss Rouen (especially the Notre-Dame Cathedral) or Bayeux (for the Bayeux Tapestry). Have lunch in Bayeux - yumm! Although it is WWII related I found visiting the German cemetery very moving. So many young men, 15, 16, 17 killed in their youth. The American cemetery is also very moving but the contrast is remarkable between the two. It's something you kinda have to experience personally to understand what I mean.

Unless you take a tour, there's no way to get around without a car. Central Paris to Bayeux, alone, is three hours - - if you know the way and don't screw up. It takes the same three hours to get back. Drivng into Rouen enroute to Bayeux makes the driving time itself four hours. Just about every village and cross-roads has some kind of museum (most are only a collection of a few relics) that are not worth seeing. In one day you don't have time to see much of anything since so much time is spent getting up and back - - maybe the Bayeux museum, the cemetery, and a beach - - but that's about it. Somewhere you've got to eat, get gas, go to the bathroom, etc. Just to pull that much off, it'd better be in the summer or you'll be chugging back to Paris in the dark.

Another option would be to train in to Rouen see that then pick up a rental car. I think the trains run almost hourly. This would be faster than driving and you can probably pick up your car at the train station in Rouen. Hopefully someone on this board has done this and will post their take on it.

'Another option would be to train in to Rouen see that then pick up a rental car.' Nope. The train takes right at an hour. You've got to get to Gare St Lazare somehow. Figure that's twenty minutes and say you only have wait ten minutes for the train and you already have your ticket in your paw. I can drive it in an hour and a half. But it doesn't matter, Rouen is another half hour, at least, off the direct track to Bayeux/Caen. Plus, there's no way you're going to fit in Rouen and the WWII stuff on the same day.

Bayeux is a great town and has such wonderful sites, e.g. Bayeux tapestry, WWII museum, the cathedral - lots to see there. We took the train from Paris to Bayeux and got a rental car there and ended up spending 3 days, 4 nights - one full day was a Battlebus tour of the WWII battlefields - spectacular. So, I would not have wanted to try and do a one dayer but I have heard some people say they take the train to Caen and from the Caen museum take a battlefield tour - I believe I remember some people saying this?