Largest ancient stones estimated at a daunting 1,650 tons (that's 3,300,000 pounds, or 1,496,850 kg).
The fully exposed block, which dates back to around 27 B.C., is the well known Hajjar al-Hibla. It's located in a stone quarry at Baalbek, site of the ancient Heliopolis in Lebanon. Similar stone blocks measuring up to 20 meters (65 feet) in length and a diameter of 4 x 4 meters (13 x 13 feet) were used for the podium of the massive Temple of Jupiter in the Roman sanctuary of Baalbek.