Kevin da Biblicalia brings us a mind-blowing Marian post that combines archeology, architecture, and the history of doctrine. From his conclusion:
It is, I think, beyond doubt that a Church of Mary Theotokos was constructed in the third quarter of the fifth century on the Temple Mount over the ruins of the Jerusalem Temple in order to commemorate the Eastern Christian tradition of Mary having grown up in the Temple itself. It may even have been at that point that the stairway and cave beneath the central rock (the former floor of the Holy of Holies) was cut, in order to provide a “luminous cave” as found in various other of the commemorated Holy Land sites … The plan of the presently standing Dome of the Rock preserves the plan of this ancient church (and perhaps even some of the structural elements?) which would have been destroyed by the Persians, along with most other churches in the Holy Land, only a few decades before the Dome itself was constructed.