Landslide in Fatimid Cairo
By Nevine El-Aref
A team of archaeologists and experts from the Supreme Council of Antiquities (SCA) examined the subsidence in an attempt to determine whether the monument itself had been damaged. The majority agreed that the cave-in was caused by the weakness of the ground on which the building stands and by the accumulation of water in the subsoil. But a minority was convinced that the reason was the construction of the nearby Al-Azhar tunnel, as well as a multi-storey underground car park in the vicinity.
"Urban development in Old Cairo is threatening the Islamic monuments in the area," said Mohamed Mahmoud, a geological expert. He explained that the ground in the area is essentially loose soil, and suffers from waterlogging in its lower levels. "Any vibrations nearby would only worsen the situation," he added.
Archaeological inspector Hossam Hamed said that the Islamic monuments of Medieval Cairo are deteriorating as a result of urban encroachment, underground water and faulty sewage facilities, as well as because of continuing problems resulting from the October 1992 earthquake. "I also believe that the use of heavy machinery in digging the Al-Azhar tunnel is one of the reasons behind the collapse of the mosque's courtyard," he said. "The vibrations caused by these machines have a negative impact on the very fragile ground on which the monuments stand, and can cause its level to change."
But this view was rejected by one of the engineers working on the tunnel. "Work on the tunnel has no relation whatsoever to the cave-in," Ahmed Helmi said. "The digging and construction are going on a long way from the area where the mosque is located."
Helmi recalled that nothing had happened to the monuments of Al-Muezz Street during the construction of the Sayeda Aisha Bridge as part of the same development programme.
Ayman Abdel-Moneim, head of the Islamic research centre for the development project of Fatimid Cairo, said that the archaeological survey revealed that the reason for the cave-in was the fact that the mosque had been built "on the remains of the western Fatimid palace which was used as the residence of the Fatimid Caliphs during the period 970-1170. These ruins comprise many serdabs [tunnels], corridors and rooms, which make excellent collection points for excess ground water."
The mosque, he added, was also built on the lowest ground level in historic Cairo, which makes it highly susceptible to any changes in the amount or density of water in the subsoil. "If a sewage pump broke in the area, for example, all the water would accumulate around the mosque and the leakage would mine the earth beneath it, ultimately altering the ground level," Abdel-Moneim said.
Gaballa Ali Gaballa, secretary-general of the SCA, agreed that soil and sewage problems lay behind the courtyard's collapse. He said that LE50,000 had been allocated to restore the courtyard and find a way of preventing similar problems in the future. "Archaeologists will also begin documenting every inch of the mosque," he vowed.
Abdalla El-Attar, head of the Islamic and Coptic department of the SCA, described the mosque as one of the most distinguished Mameluke monuments. Constructed in 1250, the mosque is located in Al-Saliba area of Al-Muezz Street, and is attached to the Sultan Qalawun complex, which consists of a palace, a madrassa (school) and a hospital.
In the 1980s, the mosque was restored by a German team in collaboration with the SCA. Last year, LE25 million was allocated for additional restoration by the Arab Contractors Company.