Kullu is a district in Himachal Pradesh, India. It borders Shimla district to the south, Mandi and Kangra districts to the west, and the Lahaul and Spiti district to the north and east. The largest valley in this mountainous district is the Kullu Valley. The Kullu valley follows the course of the Beas River, and ranges from an elevation of 833m above sea level at Aut to 3330m above sea level at the Atal Tunnel South Portal, below the Rohtang Pass. The town of Kullu, located on the right side of the Beas River, serves as the administrative headquarters of the Kullu district. The Kullu district also incorporates several riverine tributary valleys of the Beas, including those of the Parvati, Sainj, and Tirthan rivers, and thus some regions somewhat distant from the Kullu valley. The economy of the district relies mainly on horticulture, agriculture, tourism, and traditional handicrafts.