Oskemen or Ust-Kamenogorsk is the largest city in the east of Kazakhstan and the administrative center of East Kazakhstan Region of Kazakhst…Oskemen or Ust-Kamenogorsk is the largest city in the east of Kazakhstan and the administrative center of East Kazakhstan Region of Kazakhstan. The city has two official names. In the Kazakh language, its name is Өскемен/Oskemen and in the Russian language it is known as Усть-Каменогорск. Both names appear on the seal of the city.