It was a last-minute trip. We hadn't made big plans, didn't create an itinerary.   We also went camping.   A couple of years ago, in the summer of 2014, DW, my daughters, and I sat in a cozy restaurant in the H ô tel du Château, in the town of Beynac, in southwestern France. Above, the town stretched upward: upon the hilltop, Château de Beynac looked down onto the Dordogne River and our campsite, Capeyrou.   It was a pleasant dinner. We were dressed up, relaxed, having enjoyed a leisurely day of kayaking and canoeing the river, starting upstream, at Vitrac, passing the small towns and châteaux that line the Périgord.   Calmly, I told my beloved family that I was having a wonderful vacation, how I loved being back in Paris, loved the beaches and towns of Normandy and Brittany, and had loved the Loire Valley. The  Périgord had been surreal, and I couldn't wait to make our way to Carcassonne and, eventually, Provence.   But this evening, this very evening, would be my last nig...