One day trip from Paris to normandy

Where are you trying to go in Normandy? It's a big region. You can take a day trip from Paris to somewhere like Rouen by getting a train - very easy to do this. We did it in conjunction with a side trip to Giverny to see Monet's Gardens.

We also took the first train out from Paris to Carentan and met up with a private tour operator who drove us around the American sector sights (Utah & Omaha Beaches, American cemetery, etc.) and then he dropped us off in Bayeux to catch an early evening train back. It was a very long day and we all wished we could have stayed a few days to explore more, but it was still really worthwhile and I'm glad we did it. Any tour that originates straight from Paris will also be an equally long day with a lot of time spent on a coach bus. We much preferred being able to stretch out in the train and then having a private guide that brought us only to the sites we really wanted to see instead of having to stick to a predefined itinerary of a large group tour.

You can take a morning train direct from Paris to Bayeux. There are quite a few guides offering half-day tours of the major D-Day sites. Overlord Tours is always highly recommended on this forum, but there are plenty of others. We used http://normandy-landing-tour.com/, based in the Hotel de La Gare almost directly across from the Bayeux train station, a two-minute walk. Other operators will pick you up and drop you off at the train station. You can be back in Paris in time for a late dinner.

We made this trip in June 2015. It's definitely a long day and a pretty whirlwind tour. It would always be wonderful to have more time, but if one day is all you have, the trip is well worth it. We even had time to dash into Bayeux before our tour started to view the famous tapestry, one of the best installations of a historic artifact you'll find anywhere.

Do you mean a daytrip to somewhere in Normandy or are you specifically interested in the D-day beaches?

If just somewhere in Normandy, I'd suggest Rouen. It's an easy train trip, lots of direct trains. The old center is walking distance from the train station. You can see the medieval center and Joan of Arc sites, then get a direct train back.

If you mean D-day beaches, you will want to get a direct train to either Caen or Bayeux and get a half day tour from there. I've only seen Bayeux tours mentioned here but there have to be tours from Caen also. If you time it right, you might also have time to see the Bayeux tapestry before heading back to Paris. Either of these are too far out unless you get direct trains. Direct trains are available but not every train is a short trip - check the time in route, both ways, carefully before you book.

Do I need to reserve a train to Normandy
before my trip? And do you know the cost? Is there a special train that heads in that direction? Thanks

If by Normandy do you mean the D-Day beaches area? If so you can rent a car outside of central Paris, take the metro to pick up the car, drive to Normandy and spend the night. Then drive back and take the metro into central Paris. Figure about 3.5 hours drive each way. This way you you'll have time to explore and won't be rushing around too much. It's too far to drive up and back in a day if you want to have time to experience rather than see. I don't have experience with a tour but it's pretty far for an easy day trip in my opinion.

You do recognize that Normandy D-day beach area, if that is what you are interested in seeing, is roughly 50 miles east to west and 3 to 5 miles deep. Lot of area to see and long distance from Paris. Very difficult to do as a day trip from Paris.

We reserved our train tickets and printed them out before leaving home. I'm sure you can buy tickets at the station same-day, but you'll save money buying in advance. You can buy tickets and pick seats here:

https://en.voyages-sncf.com/en/

As someone else mentioned, pay close attention to the travel times when you're researching tickets. We had a direct train to Bayeux and the journey took about 2.5 hours, as I recall. Some trains go to Caen, where you have to transfer, but it looks pretty easy. Other routes can take much longer. Trains to Caen and Bayeux leave from Gare Saint-Lazare in Paris. It's easy to get to the station via the Metro. We were first-time travelers to Europe, with all the expected trepidation, and we managed just fine.

Hi mdb, this topic came up a few months ago. Here are the responses:

https://community.ricksteves.com/travel-forum/france/day-trip-to-normandy-from-paris-da33032e-03d3-4024-a9b3-709af1dab34c