KHOI, a district and town in the province of Azerbaijan, Persia, towards the extreme north-west frontier, between the Urmia Lake and the river Aras. The district contains many flourishing villages, and consists of an elevated plateau 60 m. by 10 to 15, highly cultivated by a skilful system of drainage and irrigation, producing fertile meadows, gardens and fields yielding rich crops of wheat and barley, cotton, rice and many kinds of fruit. In the northern part and bounding on Maku lies the plain of Chaldaran (Kalderan), where in August 1514 the Turks under Sultan Selim I. fought the Persians under Shah Ismail and gained a great victory.
The town of Khoi lies in 38° 37′ N., 45° 15′ E., 77 m. (90 by road) N.W. of Tabriz, at an elevation of 3300 ft., on the great trade route between Trebizond and Tabriz, and about 2 m. from the left bank of the Kotur Chai (river from Kotur) which is crossed there by a seven-arched bridge and is known lower down as the Kizil Chai, which flows into the Aras. The walled part of the town is a quadrilateral with faces of about 1200 yds. in length and fortifications consisting of two lines of bastions, ditches, &c., much out of repair. The population numbers about 35,000, a third living inside the walls. The Armenian quarter, with about 500 families and an old church, is outside the walls. The city within the walls forms one of the best laid out towns in Persia, cool streams and lines of willows running along the broad and regular streets. There are some good buildings, including the governor’s residence, several mosques, a large brick bazaar and a fine caravanserai. There is a large transit trade, and considerable local traffic across the Turkish border. The city surrendered to the Russians in 1827 without fighting and after the treaty of peace (Turkman Chai, Feb. 1828) was held for some time by a garrison of 3000 Russian troops as a guarantee for the payment of the war indemnity. In September 1881 Khoi suffered much from a violent earthquake. It has post and telegraph offices.