Tonkolili District is a District in the Northern Province of Sierra Leone. Its capital and largest city is Magburaka. The other major towns include Masingbi, Yele, Mile 91, Bumbuna, Yonibana, Matotoka. Mathora, Magbass and Masanga. Tonkolili District is home to the largest sugar factory in Sierra Leone, and one of the largest sugar factories in West Africa, that is located in the town of Magbass. Tonkolili District had a population of 530,776. The district occupies a total area of 7,003 km2 (2,704 sq mi) and comprises eleven chiefdoms.
Tonkolili District borders Bombali District to the northwest, Kono District to the east, Kenema District and Bo District to the southeast, Port Loko and Koinadugu Districts. Tonkolili is strategically located in the center of Sierra Leone. The district is criss crossed by many rivers including the Pampana River and Sierra Leone's longest river, the Rokel.