Markazi is one of the 30 provinces of Iran. The word markazi means central in Persian. Markazi lies in western Iran. Its capital is Arak. Its population is estimated at 1.35 million. The present borders of the province date to the 1980s, when the province was split into the current Markazi and the Tehran Province, with portions being annexed by Esfahan, Semnan Province, and Zanjan.