Driving from Amboise to Carcassone

Although we are train travellers, we did Amboise Sarlat and Carcassonne a couple of years ago. My advice is spend more than 1 night in Sarlat especially if you can coincide with Market Day. We found the place enchanting as was the Dordogne region. Carcassonne is something magical and definitely needs 2 days. An amazing step back into medieval times.
Can thoroughly recommend Le Pavillon des Lys in Amboise, La Villa des Consuls in Sarlat and Le Jardin de la Cite in Carcassonne. Have a wonderful time

We drove from Carcassonne to Chinon, about the same distance, in a long day. Most of it is autoroutes. Sarlat is definitely worth a stop if you have the extra night. From near Sarlat we drove to Carcassonne in about half a day. So you should have some time to explore in the Dordogne if you want, or extra time in Carcassonne if you prefer that. I'd recommend spending a night in the old city of Carcassonne, but not a full day (two nights) if you have other choices.

I wish you had more time in this area, especially if a second night near Sarlat would help you to visit any prehistoric caves.

As a quick stop along the route, Rick recommends a reminder of WWII at Oradour-sur-Glane.

It also takes only a quick stop at Cahors to see the Medieval bridge.

Closer to Carcassonne, many of us have loved the well-preserved cathedral and the Toulouse-Lautrec museum at Albi.

There's more to see nearby Carcassonne, but easier to reach while you still have the car.

These areas don't have a lot of info on this web site but are well covered in Rick's France guidebook.