South khorasan province is a province located in eastern Iran. Birjand is the center of the province. The other major cities are ferdows, Tabas and Qaen. This new province, is but the old Quhistan which was included into greater Khorasan in the Iranian administrative planning. However, historically Quhistan forms a separate entity, with a distinct culture, history, environment and ecology. South Khorasan is one of the three provinces that were created after the division of Khorasan in 2004. The most populated city and the capital of south Khorasan Province is Birjand, borders Qaen County in the north, the cities of Darmain and Sarbisheh in the east, the city of Nehbandan and Kerman province in the south and the cities of Sarayan and Tabas in the west. Birjand is one of the top producers of saffron, which is known as red gold for its commercial value, in Iran.