Tora (Egyptian Arabic: طرة Tora IPA: [ˈtˤoɾˤɑ]) was the primary quarry for limestone in ancient Egypt. The site, which was known by the ancient Egyptians as Troyu or Royu, is located about halfway between modern-day Cairo and Helwan.[2] Its ancient Egyptian name was misinterpreted by the Ancient Greece geographer Strabo who thought it meant it was inhabited by Trojans, thus the Hellenistic city was named Troia.[3] The site is located by the modern town of Tora in the Cairo Governorate.[4]