Erzurum is a city in eastern Anatolia, Turkey. It is the largest city and capital of Erzurum Province and is 1,900 meters above sea level. Erz…Erzurum is a city in eastern Anatolia, Turkey. It is the largest city and capital of Erzurum Province and is 1,900 meters above sea level. Erzurum had a population of 367,250 in 2010. It is the site of ancient Theodosiopolis.