If you have the time, take a day trip to a wonderfully atmospheric bit of the Middle Ages.
A uniquely impressive cliffside fortress town.
It's a bit farther afield from Bordeaux (140 km/87 miles away), but if you have the time, La Roque-Gageac makes a dramatic day trip indeed. Looking practically chiseled into the cliff between towering peaks and with the Dordogne River below, this fortress-town has a rough and medieval look about it. Constructed thusly to defend against invaders such as the Vikings and later the English, it's an extremely atmospheric world apart, a cross between a fishing village and an aristocratic town - so much so that it's classified as one of France's top three most beautiful towns.