TO REACH THE HOUSE Karl Fournier and Olivier Marty made for themselves outside Marrakech in Morocco, you first drive southeast for about half an hour, then turn onto a deeply rutted dirt track that makes your SUV buck and pitch (don’t even think about trying to get here in a normal car). Soon the landscape empties out, and the scattered concrete huts disappear. As the track rises toward the Atlas Mountains, it passes alongside a hidden oasis. Before long, the baked mud walls of what looks to be an empty village appear. You’re there, wherever that might be. The place has no name, just “Kilometer 33.”
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