Sarlat-la-Canéda anchors a circuit of fortified villages that condensed seven centuries of frontier warfare into honey-coloured limestone and slate. Between the 12th and 15th centuries, the Dordogne River marked the shifting border between French and English territory during the Hundred Years' War, and the valley's escarpments became a strategic chessboard. Villages like Beynac and Castelnaud faced each other across the water as rival strongholds, their châteaux alternating allegiance with each treaty and siege. Domme, founded in 1281 by Philip III as a bastide royale, perched 150 metres above the river with its grid of arcaded streets and three fortified gates still intact. La Roque-Gageac nestled against a south-facing cliff to trap winter sun and shelter subtropical gardens that survive frost-free to this day. The Dordogne villages half day tour from Sarlat departs from the medieval quarter where Saturday's market has convened since the 9th century beneath the Lantern of the Dead, a conical stone tower whose original purpose scholars still debate. Most excursions follow the D703 south to Beynac-et-Cazenac, where Richard the Lionheart seized the castle in 1189 and Simon de Montfort besieged it in 1214 during the Albigensian Crusade. The keep's double curtain walls and machicolated gallery remain among the purest examples of 13th-century military architecture in southwestern France. Across the river, Château de Castelnaud now houses Europe's largest collection of medieval weaponry, including a working trebuchet that launches 100-kilogram projectiles during summer demonstrations. Domme's limestone escarpment holds a network of caves that served as refuge during the Wars of Religion and as a clandestine market during the Revolution. The village's porte des Tours, a twin-towered gate, preserves Templar graffiti carved by knights imprisoned there in 1307 after Philip IV dissolved the order. La Roque-Gageac, ranked among France's Plus Beaux Villages, clings to its cliff in a single street, its troglodyte dwellings and Manoir de Tarde reflecting in the river below. The village was sacked by Vikings in 862, rebuilt by bishops of Sarlat in the 10th century, and partly destroyed by a 1957 rockfall that killed three residents and prompted the cliff's permanent stabilization. Guided village tours trace the Dordogne's role as a prehistoric trade route, a Roman navigation corridor, and a Renaissance transportation artery that moved Bordeaux wine and Bergerac tobacco upriver to Souillac and Argentat. The valley's golden light, filtered through morning mist and reflected off the river, attracted Henry Miller in 1934 and continues to draw painters and photographers to its September harvest season.