This has long been a place of pilgrimage—Saint Denis was decapitated here. According to legend, he picked up his head after the decapitation and carried it many miles away to be buried outside of Paris.

A statue of Saint Denis on Notre Dame's façade.

Montmartre is also home to Sacré Coeur, a basilica that incorporates both Romanesque and Gothic architecture. Curiously, it is built from a kind of limestone that whitens with rain, so that the stones get lighter over time. (-Lisa)