Bayeux to Sarlat to San Sebastian travel tips

Hi,
Your itinerary is complex, but feasible with enough time. How long do you have for the whole "thing" including Bayeux?
Regardless, here's what I can offer.
1. Assuming Paris as your port of entry, the best way to reach Bayeux is by train from Paris Saint Lazare. Best reached by taxi from CDG if you want to go straight there from an int'l flight.
2. Bayeux to Sarlat is difficult by train all the way, plus you'll want to have a car around Sarlat. So the best way to go is by train from Bayeux to Bordeaux, which can be done either via Paris, or via Caen and Saint Pierre des Corps near Tours (the latter avoids crossing Paris by metro, and is cheaper). Bordeaux where you then rent a car.
3. You might actually want to keep the car to drive from Sarlat to San Sebastián. The car is a burden in S Sebastián, but will help greatly for any exploration of the region, for which you have plenty of time in 4-5 days.
4. You then drive back across the border to return the car: Bayonne, or Bordeaux to avoid drop-off fees if applicable.

Additional note: Bordeaux is pretty, worth an overnight arriving from Bayeux.

Thanks very much for the quick advice. We have several weeks for our trip so very flexible. Is there a train from BOrdeaux to Sarlat?

For now there is no train due to track work. Not sure until when, though!

I was in the Dordogne in June, at which time the signage indicated train service would be restored before you'll be in France. I have no idea how likely they are to meet that schedule.

I don't know what you mean by "the war memorial in Bayeux". The town has a good war museum and a British cemetery. Most people who travel there want to see some of tne D-Day sites, which are not in Bayeux. For those interested in seeing sites related to the invasion, a tour is highly recommended. I fear that for most folks (not serious hobbyists or college history professors), the do-it-yourself approach could be little more than a tour of sand and chunks of concrete. The driver/guides working for companies like Overlord add a great deal of value.

Are you foodies? If you are not, I wouldn't spend so much time in San Sebastian. Bilbao is larger, with more to see. Note that the Basque Country tends to be cool and wet even in mid-summer, so you shouldn't expect typical Spanish weather in October.

We’ve been in Bayeux and Sarlat on different trips, coming from/going to different places.

For our San Sebastián (aka Donostia) visit a few years ago in October we did have a car. We used it to go to destinations nearby, but otherwise it was parked in an underground parking garage that cost something like €24 a day, and we walked 5-10 minutes to and from our car and hotel room.

One day it was pouring rain, so we visited the aquarium in San Sebastián, a nice option on a soggy day.

If you're going to be in San Sebastian, consider a day trip north into France to St. Jean de Luz. I prefer this quiet little town over Biarritz and Bayonne, although of course that's just my opinion. It's a lovely town with a nice beach and great food and shopping. Also nearby is La Rhune (mountain railway) and lovely Basque towns to the east.