The concept of Afghanistan predates the modern Afghan state and much of it consisted of the areas which are now in Pakistan. Pashtuns themselves have called this region Pashtunkhwa. Others have called it Afghanistan and Roh , the terms which have also been used by Pashtuns themselves for their country. It extended from river Helmand to river Indus and its core was Koh-i-Sulieman range.
Suleiman mountain range is very vast area and it also runs in Loy Paktiya region (Paktia, Paktika and Khost). Some people assume that Koh-i-Suliman is some range in Baluchistan province but to get an idea, it also runs in hilly portion of Dera Ismail Khan and Waziristan, and in DG Khan of Punjab. It also extends to Zabul and Kandahar. In the past, Pashtuns were called Suliamanis as Koh-i-Sulieman was their country. For example a famous saint of India, Qasim Sulimani, was a Pashtun and his disciple who wrote book on him by name of "Asrar-ul-Afghan", informs us that Pashtuns are also called Suliamanis in India. 14th century traveler Ibn-i-Batuta also say that Afghans are called Suliemanis because their abode is Sulieman range. Ibni-i-Batuta furnishes this information at the point when he come across Afghans in Kabul. Afsana-i-Shahan (written in 1607 AD) narrates the Pashtun legend that the three brothers , Baitan, Sarban and Ghurghusht (progenitors of Afghan people) lived on the banks of Gomal river in the Sulieman mountains. These few historical references and legends hints Koh-i-Suliaman to be an ancient abode of Pashtuns. Ancient Greeks have called it "Arachosia"