For nearly 180 years, both the church and the town of Saint-Denis have been without that landmark steeple. Damaged by storms, it was dismantled in 1847, supposedly so it could be built back better.

To find catacombs, go to Rome, home of some of the oldest and longest burial underground tunnels in the world. "Hundreds of kilometers of catacombs run underneath the town and its outskirts," says ...