Ancient settlements

Remains of a circular Roman tower at Babylon Fortress (late 3rd century) in Old Cairo
The area around present-day Cairo had long been a focal point of Ancient Egypt due to its strategic location at the junction of the Nile Valley and the Nile Delta regions (roughly Upper Egypt and Lower Egypt), which also placed it at the crossing of major routes between North Africa and the Levant. Memphis, the capital of Egypt during the Old Kingdom and a major city up until the Ptolemaic period, was located a short distance south of present-day Cairo.[25] Heliopolis, another important city and major religious center, was located in what are now the northeastern suburbs of Cairo.[25] It was largely destroyed by the Persian invasions in 525 BC and 343 BC and partly abandoned by the late first century BC.

However, the origins of modern Cairo are generally traced back to a series of settlements in the first millennium AD. Around the turn of the fourth century, as Memphis was continuing to decline in importance, the Romans established a large fortress along the east bank of the Nile. The fortress, called Babylon, was built by the Roman emperor Diocletian (r. 285–305) at the entrance of a canal connecting the Nile to the Red Sea that was created earlier by emperor Trajan (r. 98–115). Further north of the fortress, near the present-day district of al-Azbakiya, was a port and fortified outpost known as Tendunyas (Coptic: ϯⲁⲛⲧⲱⲛⲓⲁⲥ) or Umm Dunayn. While no structures older than the 7th century have been preserved in the area aside from the Roman fortifications, historical evidence suggests that a sizeable city existed. The city was important enough that its bishop, Cyrus, participated in the Second Council of Ephesus in 449.However, the Byzantine-Sassanian War between 602 and 628 caused great hardship and likely caused much of the urban population to leave for the countryside, leaving the settlement partly deserted. The site today remains at the nucleus of the Coptic Orthodox community, which separated from the Roman and Byzantine churches in the late 4th century. Cairo’s oldest extant churches, such as the Church of Saint Barbara and the Church of Saints Sergius and Bacchus (from the late 7th or early 8th century), are located inside the fortress walls in what is now known as Old Cairo or Coptic Cairo.

Fustat and other early Islamic settlements
A man on a donkey walks past a palm tree, with a mosque and market behind Mohamed kamal
Excavated ruins of Fustat (2004 photo)
The Muslim conquest of Byzantine Egypt was led by Amr ibn al-As from 639 to 642. Babylon Fortress was besieged in September 640 and fell in April 641. In 641 or early 642, after the surrender of Alexandria (the Egyptian capital at the time), he founded a new settlement next to Babylon Fortress. The city, known as Fustat (Arabic: الفسطاط, romanized: al-Fusṭāṭ, lit. ’the tent’), served as a garrison town and as the new administrative capital of Egypt. Historians such as Janet Abu-Lughod and André Raymond trace the genesis of present-day Cairo to the foundation of Fustat.The choice of founding a new settlement at this inland location, instead of using the existing capital of Alexandria on the Mediterranean coast, may have been due to the new conquerors’ strategic priorities. One of the first projects of the new Muslim administration was to clear and re-open Trajan’s ancient canal in order to ship grain more directly from Egypt to Medina, the capital of the caliphate in Arabia. Ibn al-As also founded a mosque for the city at the same time, now known as the Mosque of Amr Ibn al-As, the oldest mosque in Egypt and Africa (although the current structure dates from later expansions).

In 750, following the overthrow of the Umayyad caliphate by the Abbasids, the new rulers created their own settlement to the northeast of Fustat which became the new provincial capital. This was known as al-Askar as it was laid out like a military camp. A governor’s residence and a new mosque were also added, with the latter completed in 786. In 861, on the orders of the Abbasid caliph al-Mutawakkil, a Nilometer was built on Roda Island near Fustat. Although it was repaired and given a new roof in later centuries, its basic structure is still preserved today, making it the oldest preserved Islamic-era structure in Cairo today.

The Mosque of Ibn Tulun, built by Ahmad Ibn Tulun in 876–879 AD
In 868 a commander of Turkic origin named Bakbak was sent to Egypt by the Abbasid caliph al-Mu’taz to restore order after a rebellion in the country. He was accompanied by his stepson, Ahmad ibn Tulun, who became effective governor of Egypt. Over time, Ibn Tulun gained an army and accumulated influence and wealth, allowing him to become the de facto independent ruler of both Egypt and Syria by 878. In 870, he used his grow