Achinsk () is a city in Krasnoyarsk Krai, Russia, located on the right bank of the Chulym River near its intersection with the Trans-Siberian Railway, west of Krasnoyarsk. It has a population of 109,155 as of the 2010 Census. History Achinsk is one of the oldest known inhabited places in the area. Paleontological study has shown that people lived here as early as 28,000–20,000 BCE. Some of these ancient caves are located east of the city. The modern city, however, was founded on July 25, 1641 as an ostrog on the Bely Iyus River. After the fire of 1683, it was moved to the Chulym River (a tributary of the Ob); hence, the official foundation date of the city is considered to be July 25, 1683. The name of the location derives from the Turkic tribal group Achi or Achigi. The first fort in 1683 was built with the high stockade square shaped walls. In the corners were placed watch towers. Initially the garrison had fifteen Cossacks patrolling it. In 1710, a new wooden fort on the right bank of the Achinki River was created, at its confluence with the Chulym. In 1782, it was granted status of an uyezd town. In the late 19th century, the town became linked on the Trans-Siberian Railway. Since 1990, Achinsk has been included in the official list of cities in Russia with historical and cultural value of nationwide significance. In August 2019 a massive explosion in a military base () occurred some 20 km south of the town, next to the village of Kamenka. Administrative and municipal status Within the framework of administrative divisions, Achinsk serves as the administrative center of Achinsky District, even though it is not a part of it. As an administrative division, it is, together with one urban-type settlement (Mazulsky), incorporated separately as the krai city of Achinsk—an administrative unit with the status equal to that of the districts. As a municipal division, the krai city of Achinsk is incorporated as Achinsk Urban Okrug. Demographics Achinsk grew rapidly in the 20th century: from a population of 32,000 in 1939, to 85,000 in 1969, to 121,572 in the 1989 Census. The population declined slightly in the early 21st century: 118,744 (2002 Census) and 109,155 (2010 Census). Economy The economy of Achinsk is based around heavy industry and contains a refinery and also produces construction materials, including wood, asphalt, cement. Mechanical,