Chips of bone and dirt tumble out. "I love the patina—not all white and clean," he says. Behind the neat stack of skulls, tibias, and femurs in the Paris catacombs lies a chaos of bones.

Workers at the historic catacombs of Paris are rebuilding a wall containing remains of martyrs from the French Revolution. The massive underground gravesite houses up to 7 million bodies ...

Last year, a man living in the southern suburbs of Paris was renovating his basement when he made an eerie discovery: a ...