There is no archaeological evidence that Mecca even existed in the 7th cen. Mecca is described in later Arab historical accounts as an oasis and trade center. In reality, it was a waterless, barren place in the 7th century. The well Zamzam is a feeble source of water that could not have possibly supplied the needs of caravans and today is a dry hole that must be continually and artificially re-filled during the hajj.
Interesting. Never underestimate the ability of the Arabs to wipe out history and overexploit a resource.