section_path: Interior/Entrances/Robbers' Tunnel
section_name: Robbers' Tunnel
paragraph_text: Robbers' Tunnel
  
  Today tourists enter the Great Pyramid via the Robbers' Tunnel, which was long ago cut straight through the masonry of the pyramid. The entrance was forced into the 6th and 7th layer of the casing, about 7 metres (23 ft) above the base. After running more or less straight and horizontal for 27 metres (89 ft) it turns sharply left to encounter the blocking stones in the Ascending Passage. It is possible to enter the Descending Passage from this point but access is usually forbidden.
  
  The origin of this Robbers' Tunnel is the subject of much scholarly discussion. According to tradition the opening was made around 820 AD by Caliph al-Ma'mun 's workmen with a battering ram. The digging dislodged the stone in the ceiling of the Descending Passage that hid the entrance to the Ascending Passage, and the noise of that stone falling, then sliding down the Descending Passage alerted them to the need to turn left. Unable to remove these stones, the workmen tunneled upwards beside them through the softer limestone of the Pyramid until they reached the Ascending Passage.
  
  Due to a number of historical and archaeological discrepancies, many scholars (with Antoine de Sacy perhaps being the first) contend that this story is apocryphal. They argue that it is much more likely that the tunnel had been carved shortly after the pyramid was initially sealed. This tunnel, the scholars continue, was then resealed (likely during the Ramesside Restoration), and it was this plug that al-Ma'mun's ninth-century expedition cleared away. This theory is furthered by the report of patriarch Dionysius I Telmaharoyo, who claimed that before al-Ma'mun's expedition, there already existed a breach in the pyramid's north face that extended into the structure 33 metres (108 ft) before hitting a dead end. This suggests that some sort of robber's tunnel predated al-Ma'mun, and that the caliph simply enlarged it and cleared it of debris.