CAIRO - The Mosque of Ibn Tulun is only remaining monument in the City of Qata'i', established in AD 870 as the capital of the Tulunid state in Egypt. It is the second oldest mosque extant in Egypt and the third largest mosque in the world. The mosque, which he had built over a period of three years of mud-brick on top of a hill known as Gabal Yashkur, became the focal point of the Tulunid capital. Ahmad Ibn Tulun built this mosque from 870 to 879 AD in order to accommodate all of his troops. Ibn Tulun was the son of a Turkish slave of Mongol origins owned by the Abbasid Caliph al-Ma'mun. From these humble origins he rose to great power, founding the Tulunid Dynasty (868-905 AD) of Egypt. After becoming the ruler of Egypt, Ibn Tulun founded a new city called al-Qata'i (now Sayeda Zeinab district of Cairo) on a rocky outcrop. When the Abbasids regained power in AD 905, Ibn Tulun's city was razed, but the great mosque at its centre was spared. However, the city centre shifted away from the rock and the mosque fell into neglect. In the 12th century it was used as a shelter by pilgrims, which caused some damage and some sources say that it was used as horse stable. In 1296, the Mamluk Sultan Hosam al-Din Lajin restored the Ibn Tulun Mosque and made some innovative additions. He had been a conspirator in the assassination of Sultan al-Ashraf Khalil ibn Qalawun and had hid in the deserted mosque, vowing to restore it if he escaped with his life. It was also renovated in later periods, and the Supreme Council for Antiquities undertook a complete if not entirely uncontroversial restoration of the complex in the first decade of this century. Actually, this magnificent mosque reflects all the characteristic features of Abbasid art within the realm of architecture, and was obviously influenced, particularly with regard to the minaret, the great rectangular piers with engaged corner columns, the decorative motif and other features by the famous Samarra mosque in Iraq (the capital of the Abbasid state during AD 836–92). On entering the mosque and ascending some steps, then reaching the expansive sahn (courtyard) in its centre you find an ablutions fountain, an innovation of Sultan Lajin. Four porticoes surround the courtyard, the largest is the eastern portico (that of the qibla - the direction to Mecca) consisting of five arcades; each of the other three porticoes consists of two arcades. The exterior façades of the building are strikingly crowned by crenellations composed of distinctive forms resembling children holding their hands together. On the north, west and south sides, a large wall surrounds the mosque. Between these walls and the walls of the building is an open area called the ziyada, an example which recalls the Great Mosque of Samarra in Iraq, built in AD 850. The upper part of the mosque walls has 128 pierced-stucco arched windows with geometric and interwoven vegetal decorations, executed in marble. These stucco windows are considered one of the most exquisite characteristics of the building, since each window differs from the other in the layout of its decorative motifs. In fact, this is the first example of its kind in Egypt. Because of its vast area and the absence of microphones at that time, the mosque has three places for dekket el-Monadi (those who repeat the imam's words during athan). The original mosque has its madiaa (ablutions fountain) in the area between the inner and outer walls, but the distinctive fountain in the centre of the courtyard with a high drum dome was added by Sultan Lajin at the end of the 13th century. Sultan Lajin also had a clock constructed in the shape of a dome with 24 small windows representing the hours of the day. The minaret, the only one of its kind in Egypt, is modelled after the minarets of Samarra, with a spiral staircase that winds itself around the outside body of the minaret and not within the interior, as is typical of most mosques in the Islamic world. A wonderful experience to view Cairo and other celebrated old mosques from above is attainable from the minaret. It is easy to ascend the winding outside steps, some of which are wide while others are narrow, but take care to focus on your upwards or downwards climb, and not be distracted by the tantalising glimpses of the environs of this sublime mosque. Ibn Tulun Mosque is located in Saliba Street, Sayyeda Zeinab district of Cairo. It is open daily from 9 am to 4 pm.