I want to go to this church sometime. This is how it is described:
Perhaps one of the most remarkable sights in France, a chapel perched on a volcanic plug. This is the Rock of Aiguilhe, on the edge of the town of Puy en Velay, in the Auvergne. The Chapelle Saint-Michel has stood there for 1042 years, since Bishop Gothescalk had it built in 962 on his return from a pilgrimage to Santiago del Compostella in Galicia. In 1955 workers found relics under the alter that had been there since it was built.
(via Bored Panda)