Children go to sleep in a day school during the day in the polar summer. The sun doesn't set for around 45 days which can make people disorientated and cause sleep disorders.
The city of Norilsk, in the far north of Russia's Krasnoyarsk region, was founded in the 1920s and today has a population of just over 175,000. In its early years it served as the centre of Norillag (or the Norilsk Corrective Labour Camp) but was given town status in 1953 as the Gulag system was slowly winding down. Today the city is largely dependent on MMC Norilsk Nickel, the world's leading producer of Nickel and palladium and Norilsk's main employer. In 2001, the city was closed to all non-Russians, except for citizens of Belarus.