Excavation on the citadel mound from the late 1990s uncovered a temple of the storm god that had stood there for something like two thousand years, from the early second millennium BCE onward, with basalt reliefs showing the god in his chariot and a procession of figures along the walls. Aleppo, called Halab in texts from Mari and from the Hittite archives, was the seat of a kingdom whose god was invoked in international treaties, and Hittite kings recorded taking oaths by the storm god of Halab. That gives the mound one of the longest documented sequences of continuous worship anywhere in the Near East.
The temple site is now occupied by a small mosque associated with Abraham, and the popular etymology of the city's name from the milking of Abraham's cow belongs to the same layer of tradition, a folk explanation attached to an older sanctuary rather than a historical account.
Below the citadel the Great Mosque was founded under the Umayyads and rebuilt repeatedly, and its free standing minaret of 1090, one of the finest pieces of Seljuk period architecture in Syria, collapsed in the fighting in 2013. The old city also held churches of the Greek Orthodox, Syriac Orthodox, Armenian Apostolic, Maronite and Chaldean communities in the Jdeideh quarter, and a Jewish quarter with several synagogues. Much of that fabric was destroyed between 2012 and 2016, and much of the population that used it has left.