The ancient site at Kot Diji (Urdu: کوٹ ڈیجی) was the forerunner of the Indus Civilization. The people of this site lived about 3000 BCE. The remains consist of two parts; the citadel area on high ground (about 12 m), and outer area. The Pakistan Department of Archaeology excavated at Kot Diji in 1955 and 1957.

Located about 22 kilometers south of Khairpur in the province of Sindh, Pakistan. The site is situated at the foot of the Rohri Hills where a fort (Kot Diji Fort) was built around 1790 by Talpur dynasty ruler of Upper Sindh, Mir Suhrab who reigned from 1783 to 1830 AD. This fort built on the ridge of a steep narrow hill is well preserved.

The development of these farming communities in different parts of Baluchistan and Lower Sind, ultimately led to urbanization. The earliest fortified town to date is found at Rehman Dheri, dated 4000 BCE in NWFP close to River Zhob Valley. Other fortified towns found to date are at Amri (3600-3300 BCE) and Kot Diji in Sind and at Kalibangan (3000 BCE), India at the Hakra River. No writing were found at these sites.