Lyok is a village in the Zangazur uezd of the former Yelizavetpol (Ganja) governorate, later in the former Mehri (Meghri) district, and present-day Syunik province. It lies 56 km to the northeast of the provincial centre, on the left bank of the middle branch of the Mehri River, at a height of 1,814 meters above sea level. Some sources indicate that the village of Lyok consisted of Ashagi Lyok and Yukhari Lyok.

The village was inhabited by 136 Azerbaijanis in 1831, 316 in 1873, 480 in 1886, 506 in 1897 and 1,053 Azerbaijanis in 1914. In 1918 Andranik’s gang destroyed 100 houses in the Ashagi Lyok village and 60 in the Yukhari Lyok village and killed 200 people. After that, the Lyok village was abandoned for several years and turned into ruins. Following the establishment of the Zangazur uezd in Soviet Armenia on 31 August 1921, the settlement was integrated into the administrative area of Armenia. Following the establishment of Soviet power in Armenia, the Azerbaijani population of the villages of the district gradually began to return to their native lands. In 1922 only 177 out of 1,053 inhabitants of the Lyok village returned to the village. This figure reached 187 in 1926, and 243 in 1931 respectively. In 1988 there were 90 houses in the village. It was inhabited by 600 Azerbaijanis. In November 1988, through the punitive measures of the administrative bodies of the district, Armenians forced the villagers to flee within a week, having no mercy on children, women and the elderly.

By the decree of the Presidium of the Supreme Soviet of the Armenian SSR dated 18 June 1960, the village was renamed “Vartanidzor”. According to the law “On the administrative-territorial division of the Republic of Armenia” dated 7 November 1995, it was integrated into the administrative area of the Sunik province.

Geographical coordinates: latitude: 38°58’ N., longitude: 46°12’ E.