Visit on a holiday if you can.
"L'abbaye Saint-Pierre de Brantôme"
The Benedictine Abbey of Brantôme was founded in 769 on order of Charlemagne in honor of Saint Pierre (Peter) and Saint Sicaire. It is particularly interesting to visit the "troglodyte" part of the abbey that was carved out of the cliff. Of course you are in cave country so it all fits into the theme.
The cloister and church are worthy of a visit and the clock tower is hard to miss since you can see it all over town.
We were there two days before May Day which is Labor Day in France and a major holiday so they were setting up a carnival between the abbey and the river. It was great fun but didn't do much for my photos. ;^)
"Free, shaded parking by the river"
We drove through town, across the river and followed signs to parking. This is shaded and adjacent to a canoe rental business. On a warmer day, renting a canoe would be great fun and the Dronne River is stunning.
Take the time to walk around town after you visit the abbey because the town is quaint, colorful and very friendly.
"Take a walk through town"
There are the usual businesses and there are tourist shops. Both are fun to visit. This quaint chocolate shop is lots of fun. We visited the local boulanger for our evening baguette and everyone there was incredibly friendly, telling us all the things we could visit in the area. (The bread was good too.)