The Basilica of Saint Denis is a large medieval abbey church in the city of Saint-Denis, now a northern suburb of Paris. it is considered to be the first Gothic church every built.
The site originated as a Gallo-Roman cemetery in late Roman times. The remains still lie beneath the present cathedral.Around 475 St Genevieve purchased some land and build a chapel. It is the burial place of nearly every French king from the 10th to the 18th century as well as many kings from previous centuries. There are too many to list here. Check wikipedia for a complete listing.