The Dordogne is said to have 1001 castles. Many of these are not open to the public, however, and also the name 'chateau' can be applied to any house that has been a centre of wine production - so many places that are called 'chateaux' will be distinctly less imposing than others.
Be that as it may, the Dordogne region has many of the finest castles in France, often in spectacular locations, and frequently surrounded by carefully manicured gardens with far-reaching views over the Perigord countryside.
Many of the castles date from the turbulent times and wars between England and France in the 12th-14th centuries during the Hundred Years War and typically still in their medieval condition(by contrast with the Loire Valley castles which were often transformed during the renaissance period).
Aquitaine: Dordogne Chateau
Chateau de Beynac (Dordogne)
Chateau de Biron (Dordogne)
Chateau de Bonaguil (Lot-et-Garonne)
Chateau de Bourdeilles (Dordogne)
Chateau de Castelnaud (Dordogne)
Chateau de Commarque (Dordogne)
Chateau de Fumel (Lot-et-Garonne)
Chateau de Gavaudun (Lot-et-Garonne)
Chateau de Hautefort (Dordogne)
Chateau de Jumilhac (Dordogne)
Chateau de Losse (Dordogne)
Chateau de Montfort (Dordogne)
Chateau de Puyguilhem (Dordogne)
Chateau de Puymartin (Dordogne)
Chateau des Milandes (Dordogne)
Map of Dordogne Castles
Actually I have cheated a bit, because some of these castles are across the southern border of the Dordogne region and are actually in the Lot-et-Garonne department. All are easily visited on a visit to the Dordogne region however.
We now also have a section dedicated to France castles where you can learn more about castles in all regions of France.