Wikipedia
Dalstroy (, ), also known as Far North Construction Trust, was an organization set up in 1931 by the Soviet NKVD (the predecessor of the KGB) in order to manage road construction and the mining of gold in the Chukotka region of the Russian Far East, now known as Kolyma. Initially it was established as State Trust for Road and Industrial Construction in the Upper Kolyma Area. After the 1952 reorganization it was known as Main Directorate of Camps and Construction of the Far North.
Dalstroy oversaw the development and mining of the area using forced labor (slave labor). Over the years, Dalstroy created some 80 Gulag camps across the Kolyma region. As a result of a number of decisions, the total area covered by Dalstroy grew to three million square kilometers by 1951. The town of Magadan was the base for these activities.