The Abbaye de Cluny was at one time the largest church in Christendom but only one tower remains after it was expropriated during the French revolution and sold one stone the time. Do take the tour (guided or not) that includes the adjacent palais of Jean de Bourbon. For an online preview of the site, please access: http://www.sacred-destinations.com/france/cluny-abbey
Also, numerous...
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