Quote: (Cairo) The unique Magra El-Oyom ancient wall was originally constructed approximately 800 years ago with the purpose of directing water from the Nile to the Salah Eddin Castle. It is a brilliant example of ancient Islamic engineering as it mechanically pumps water from the Nile (via water wheels) and carries the water over the course of 2km inside the wall to service the castle with its water needs. The wall is hollow in a few portions acting as a giant ancient stone water pipe system, but the main course of water flows along the top of the wall within a trench cut channeled grove. Remarkable also is the designer's ability to channel water on an upwards incline to reach the Salah Eddin Castle which sits on a hill. Dr. Gaballah Ali Gabballah, head of the Supreme Council of Antiquities, gives a brief history about the wall: "The wall was built by Sultan Salah Eddin El-Ayuby. The purpose of this wall is to direct water coming from the Nile onwards up the hill where his Castle was built. The wall was built in 1193 AD. Nile water would pass through channels built on vaults in the Fom El-Khalig area till it reaches water wheels where it is then directed to its storage in deep castle wells. After numerous decades, these water wheels became non-functional and were neglected. Later, Sultan Mohamed Ben Kalawon repaired the wheels in two stages. The first stage was in 1310 AD. Six water wheels were built near El-Habash Lake. These water wheels would lift the Nile water to channels and from the channels to wells; wells which can still be seen to this day. The second stage of the Sultan's restoration effort was in 1340 AD. A massive well was dug in El-Habash Lake, which is known today by the name of Establ Antar. Later on, Mohammed Ali Pasha converted this well into a artillery depot. The wall structure lies south of the Salah Eddin Castle. It starts from Sayed Aisha Square where there is the ancient Al-Karafa City Gate. Then the wall extends more south till it meets the Fom El-Khalig water channel. Then the wall reaches to the El-Safah City Gate then to the Zwayala City Gate. The wall then extends up to the Ain El-Sera hills down to El-Foustat antiquities area. Then the wall ends at the El- Kantara City Gate on the Nile. The entire length of the wall covers an area of 2.2 kilometers."