train to caen or renne for Mt st michel, then DD ay beaches area

Bechteljs: It's somewhat hard to answer since it is unclear how many days you have, how large your party is, and what your travel intentions are. So, take my recommendations with a grain of salt. I have done the round-trip train from Paris to Bayeux and I have driven to Normandy (from Lille) and returned to Paris by way of Chartres, where I dropped off the rental car and took the train back into Paris.

Having a car to visit the D-Day sites gives you the flexibility to chose where you want to go; however, I would strongly recommend that you take advantage of the various tours that are available and not drive yourself. You will not only get a well-researched overview, but you will not have to waste time figuring out how to get to various sites, how much time to spend, where to park, etc. Spend some time in advance to research what museums and beach sites you are most interested in, and find a tour that visits all or most of them.

While in the area, go to Bayeux and visit the Bayeux Tapestry.

Mont St. Michel is a neat place to visit; just be aware that from mid-morning to late-afternoon you will be shoulder-to-shoulder with a lot of tourists on very narrow alleys leading up to the Abbey. We stayed the night on MSM proper and enjoyed the peace and quiet and the sights after the tourist buses left. You will need to coordinate with your hotel regarding the location of the car park area for overnight visitors. Also, coordinate with your hotel ahead of time if you need to leave MSM early in the morning. The MSM shuttle bus system doesn't start until around 08:00 a.m. but I believe they may do an earlier shuttle if you need to depart early.

We visited Chartres after being at MSM on our way back to Paris. A thoroughly enjoyable visit. You will have to decide whether visiting Chartres works best on the outbound or return portion of your trip. We elected to turn the rental in at Chartres and just take an hourly train back to Paris.

Anyway, good luck and safe travels,

Trains are certainly not free and the more people who are traveling, the more that ticket price is multiplied. If you take trains and rent a car on the same day, you can in some sense be "double-paying." Car rental rates may be the same whether you keep the car for 1, 2, or 3 days, calculated based on 24 hours from pick-up time (e.g., 10:00 a.m. to 10:00 a.m.). Other peeps on this forum have suggested car pick-up locations in Paris which are relatively close to the ring road, so you avoid navigation on the "surface streets." For drive time and AutoRoute toll estimates, see www.viamichelin.com.

While in Normandy-stay in Bayeux - great town, tapestry is very interesting, good food, The Churchill Hotel is tops in our book. Adequate parking and when we got a flat tire the hotel called someone to come help us. Delicious breakfast; in fact, folks from other hotels were coming in to have their breakfast at the Churchill.
The hotel has a van that takes you to Mt St M for the day...very interesting driver tells you lots of interesting facts on the way. Lunch in MStM was great and uncrowded in a little upstairs crepe restaurant. Yes, it is full of tourists, but if you just want to see it while in Normandy area, this is the way to go. We had a rental car and did the beaches, the 360 degree movie, Caen Museum....easy driving. Countryside reminded us of New England. Stop and have some cider or brandy at one of the small farms. Can't wait to go again and will do it exactly the same way!

We took the train out of Paris to Caen, rented the car almost across from the train station, then drove to the beaches area. When we returned to Caen with the car, we saw the museum and had lunch there (just sandwiches and salads, but adequate and convenient) then took the car back and trained back to Paris.

Another vote for the Churchill in Bayeux. We trained to Caen (15 Euro a ticket) and picked up a car there and drove to MSM, stayed the night and drove to Bayeux for two days the next day and then on to Honfleur for two nights traveling to Etretat on the full day, and then back to Caen and trained back to Paris. Our snapshots for some of this.
https://janettravels.wordpress.com/category/normandy/

You have a report on taking the Churchill van to MSM and that sounds like a decent option; we drove and found that easy and pleasant. However we did get a tour for the beaches; we used the Overlord all day tour which took us to Omaha, Point du Hoc, the American Cemetery, the Airborne Museum and other towns and beaches. We had decided on this trip last minute when our apartment could not take us in Paris until October and we had 5 extra nights. We hadn't done our homework and it was just easier to let Overlord plan and execute the beach tour -- we are not generally tour people but this one was very satisfying. It looked to us that it could easily be done by car however if you do the planning ahead.
Note that the Churchill MSM trip is in a small van and books out well ahead, so if you want to do that be sure to book well ahead.

In your shoes I might well just get the car in Paris and save train fares especially if there are several in your party. If you are not just arriving from an overnight flight then driving will save money and you can work in shorter stops as you go e.g. Rouen is a great 3 or 4 hours stop; the central historic district is small and you can see the major churches and the architecture in a short stop. Chartres is another place where 3 or 4 hours has real pay off.