(Click to enlarge images) A selection of altars and retables from the ambulatory chapels of Saint Denis. Most of these appear medieval. Unfortunately I cannot say with certainty. Abbot Suger wrote of a "symphony of masses" following the consecration and it is not difficult to imagine these altars being used, however, much restoration is said to have taken place under Viollet le duc in the nineteenth century. I am always delighted to see the altar stone set into the mensa as in the above examples. Marked with five crosses recalling the five wounds they serve to seal in the relics. The tradition of setting the relics of martyrs in the altar is very ancient, recalling the passage in the Apocalypse where the voices of the martyrs are heard from beneath the altar. At the recent exhibition about relics and reliquaries (at the British Museum) I learned that the Second Council of Nicaea (787) decreed that no altar should be consecrated without relics.
The other interesting feature in each of these pictures is the retable. The retable, reredos or, elsewhere, altarpiece painting are the varied forms of what appears to be a twelfth century development.