Visiting the Prehistoric Wonders
Perhaps the Dordogne’s most famous sights are its prehistoric caves and grottos, with the legendary Lascaux topping the list. It’s been closed to the public since 1963, but many others are open for viewing. Lascaux II—a near-perfect replica—can accept up to 2,000 visitors a day; on the other hand, the Grotte des Combarelles takes only 40 in total and no more than six on any given tour, thereby guaranteeing an intimate look.
Either because demand far outstrips supply, or because tickets are so limited, it's recommended that you call or email to prebook tickets whenever possible. For places like Lascaux II, reserve as far ahead as you can (up to a year). For less popular sights, a couple of days should suffice. Alternately, you can try signing up for a day-of tour first thing in the morning.
The main tourist offices in the region, such as the one at Les Eyzies-de-Tayac, have the lowdown on all the caves and prehistoric sights in the area. If you can’t secure tickets in advance, it's worth stopping by the cave of your choice even if the office says they are sold out, as space often opens up. Be forewarned: you might get signed onto a tour that starts in a couple of hours, leaving you with time to kill, so have a game plan handy for other places to visit nearby.