Chapelle St-Michel d'Aiguilhe Auvergne

Le Puy's oldest chapel, first established in the 10th century, and rebuilt several times since, teeters atop an 85m-high volcanic plug, reached by climbing 268 craggy stairs. Stepping through its polychrome doorway into the cave-like interior is a near-mystical experience – the chapel follows the natural contours of the rock, and the unusual carvings and 12th-century frescoes create an otherworldly atmosphere.