From the Wikipedia page [1]
Balagansk (Russian: Балага́нск) is an urban locality (a work settlement) and the administrative center of Balagansky District of Irkutsk Oblast, Russia. It is located on the left bank of the Angara River, downstream from Svirsk and 285 kilometres (177 mi) by road northwest of Irkutsk[8] and to the southeast of Sayansk. Population: 4,109 (2010 Census);4,307 (2002 Census); 4,136 (1989 Census).
On three sides of Balagansk is the Bratsk Reservoir. The settlement is best known for Balagansk Prison, which was used as one of the Siberian exile camps during the Stalin era.