Tayk (Armenian: [[wikt:Տայք|Տայք]], {{IPA-hy|tajkʰ) was a historical province of the Kingdom of Armenia, one of its 15 (worlds). Tayk consisted of 8 cantons:
There was a proto-Armenian confederation, Hayasa-Azzi, in this area in the 2nd millennium BC. It was probably the same as (and with a name likely related etymologically to) the Daiaeni and Diauehi of Assyrian and Urartian sources. From the 2nd century BC to the 9th century AD Tayk was a part of Armenian kingdoms or "autonomies": Greater Armenia, Marzpan Armenia and Bagratid Armenia.
In the 999 A.D., Tayk or Tao became part of the Georgian Bagratid principality of Tayk-Kharjk or Tao-Klarjeti. The Tayk province covered the contemporary Turkish districts of Yusufeli (Kiskim) in Artvin Province and Oltu, Olur (Tavusker), Tortum and Çamlıkaya (Hunut) to the north of İspir in Erzurum Province. To its southwest is found the ancient region of Sper. After World War I, Armenia and Georgia contested the region, with particular conflict over Oltik. As a result, in 1920, after the Russo-Turkish attacks Armenia lost the region of Oltik, which become a part of Turkey.