Haydarli or Heydarli is a village in the Alexandropol uezd of the former Iravan governorate, later in the former Boyuk Garakilsa (Gugark) district, and currently in the Lori province. It is located 2 km to the northwest of the Hallavar village, on the banks of small rivers called “Hallavar” and “Boyuksu”, at a height of 1,600 m above sea level. It was marked on the five-verst map of the Caucasus.

The village was inhabited by 26 Azerbaijanis in 1831, 158 in 1873, 175 in 1886, 265 in 1897, 357 in 1908, 461 in 1914, 343 in 1916 and 1,328 Azerbaijanis in 1919. In 1919, the villagers, the Azerbaijanis, were attacked by Armenian armed forces and deported. The surviving Azerbaijanis managed to return to their historical lands following the establishment of Soviet power in present-day Armenia. It was inhabited by 294 Azerbaijanis in 1922, 324 in 1926, 398 in 1931, 496 in 1939, 448 in 1959, 994 in 1970 and 1,350 Azerbaijanis in 1987. In November-December 1988 the Azerbaijanis were deported from their historical and ethnic lands.

The toponym was formed on the basis of the name of the Heydarli tribe.

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 Lori province.

Geographical coordinates: latitude: 40°47’ N., longitude: 44°23’ E.