The unfinished obelisk is the largest known ancient obelisk and is located in the northern region of the stone quarries of ancient Egypt in Aswan (Assuan), Egypt. Archaeologists claim the pharaoh known as Hatshepsut sanctioned its construction. It is nearly one third larger than any ancient Egyptian obelisk ever erected. If finished it would have measured around 42 m (approximately 137 feet) and would have weighed nearly 1,200 tons.
More than a century ago, Greek divers off the island of Antikythera retrieved a mysterious object containing gears and covered with inscriptions. Called the Antikythera mechanism; the oldest known analog computer dating to around 100 BC and was used to calculate astronomical positions, and is thought to have been used to predict movements of the sun, moon and planets and record dates of the ancient Olympiad. It was the recent subject of a NOVA documentary on PBS.