The Greater Nile Petroleum Operating Company, GNPOC, is a Sudanese oil and gas exploration and production firm. It began construction of the Greater Nile Oil Pipeline, which connects Sudan’s inland oil reserves with refineries in Khartoum and Port Sudan. In June 1999, GNPOC began its oil production operations. Khartoum Tower, a nine-story building in Khartoum, Sudan, houses the company’s headquarters. GNPOC produces almost 300,000 barrels of oil per day from eight primary oil fields: Heglig, Unity, El Toor, El Noor, Toma South, Bamboo, Munga, and Diffra.