Cyrrhus (ˈsɪrəs; Κύρρος Kyrrhos) is a city in ancient Syria founded by Seleucus Nicator, one of Alexander the Great's generals. Other names for the city include Coricium, Corice, Hagioupolis, Nebi Huri (نبي هوري), and Khoros (حوروس Ḳūrus). A false etymology of the sixth century connects it to Cyrus, king of Persia due to the resemblance of the names. The former Roman/Byzantine (arch)bishopric is now a double Catholic titular see.
Its ruins are located in northern Syria, near the Turkish border.
It lies about 70 km northwest of Aleppo and 24 km west of Killis, in Turkey. Cyrrhus was the capital of the extensive district of Cyrrhestica, between the plain of Antioch and Commagene.
The site of the city is marked by the ruins at Khoros, 20 km from Azaz, Syria, standing near the Afrin Marsyas River, a tributary of the Orontes, which had been banked up by Bishop Theodoret.
The Cyrrhus in Syria was founded by Seleucus Nicator shortly after 300 BC, and was named after the Macedonian city of Cyrrhus. Andronicus of Cyrrhus built the Tower of the Winds in Athens.
It was taken by the Armenian Empire in the 1st century BC, then became Roman when Pompey took Syria in 64 BC. By the 1st century AD, it had become a Roman administrative, military, and commercial center on the trade route between Antioch and the Euphrates River crossing at Zeugma, and minted its own coinage. It was the base of the Roman legion Legio X Fretensis. The Sassanid Persian Empire took it several times during the 3rd century. Following these attacks the city became a major point of strategic importance for the Romans, who would rapidly develop and fortify it.
In the 6th century, the city was further embellished and strengthened by Byzantine Emperor Justinian, who oversaw work that only added to the Cyrrhus' already incredibly formidable defenses. It was however taken by the Muslims in 637 AD, as the Byzantines were too weak to defend it. It was then known and identified from that time under the name of Qorosh and later by the Crusaders in the 11th century.