South Khorasan province (Persian: استان خراسان جنوبی) is one of the 31 provinces of Iran, located in the eastern part of the country. Its capital is the city of Birjand. In 2014, the province was placed in Region 5. This province is bordered to the north by Razavi Khorasan Province, to the northwest by Semnan Province, to the west by Isfahan and Yazd Provinces, to the south by Kerman Province, and to the southeast by Sistan and Baluchestan Province. The area of this province is 151,913 square kilometers (58,654 square miles), making it the third largest province in Iran after Kerman and Sistan and Baluchestan. According to the 2016 census, South Khorasan's population is 768,898, making it the fourth least populous province in the country. With only about 5 inhabitants per square kilometre or 13 inhabitants per square mile, it is the most sparsely populated province in Iran.
South Khorasan Province is split into two distinct regions: the "mountainous and elevated" areas in the north and northwest, and the "low and flat" central and southern plains. The tallest mountains in the province include "Kamarak" and "Shah Kuh." It experiences a "dry and desert" climate, which can be further divided into "hot and dry" and "mild and dry" categories. The northern and northwestern parts are more fertile, while the southern and southwestern plains endure a dry and harsh climate. The rivers in this region are seasonal, with no permanent rivers present.
