- Masasi City is a city located in the Mtwara Region of Tanzania, in East Africa. It is the administrative center of the Masasi District. The city is situated approximately 500 kilometers south of Dar es Salaam, the largest city in Tanzania. Masasi City is known for its agricultural activities, with farming being the main source of income for many residents. The city has a population of around 67,000 people, and its economy mainly revolves around agriculture, fishing, and small-scale trading. Masasi City is also home to various cultural and historical sites, including the Masasi Mission, which was established by German missionaries in the late 19th century.