The modern city, however, was founded on July 25,[citation needed] 1641[2] 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.

In 1710, a new wooden fort on the right bank of the Achinki River was created, at its confluence with the Chulym.

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 (Russian: 60-й Инженерно-Сапёрный Берлинский Краснознамённый полк, в/ч 12202) occurred some 20 km south of the town, next to the village of Kamenka.

[3]The economy of Achinsk is based around heavy industry and contains a refinery and also produces construction materials, including wood, asphalt, cement.

The largest enterprise of the city, the Achinsk Alumina Plant, belongs to the "Rusal" group.