Stone Town or Mji Mkongwe, in Swahili, is the old part of Zanzibar City, the capital of the island of Zanzibar, a part of Tanzania.

The old town is built on a triangular peninsula of land on the western coast of the island. It consists of a warren of narrow alleys to houses, shops bazaars and mosques. Transport around town is by foot, bicycle or motorbike: cars are too wide to drive down many of the inner streets.

Its Swahili architecture incorporates elements of Arab, Persian, Indian, European and African styles. The Arab houses are particularly noticeable because they have large and ornately carved wooden doors and other unusual features such as enclosed wooden verandas.

The site has probably been occupied for around three centuries with buildings only being constructed with stone since the 1830s.

Two large buildings dominate the main front of Stone Town. One is Beit-El-Ajaib or the House of Wonders, which was built by Sultan Seyyid Barghash as a grand palace for ceremonial purposes. The other is the Arab Fort which stands on the site of a former Portuguese settlement and was converted to a fort during the 18th Century.

The town was the centre of trade on the East African coast between Asia and Africa before the colonization of the mainland in the late 1800s after which the focus moved to Mombasa and Dar es Salaam. The main export was spices and particularly cloves. For many years Stone Town was a major centre for the slave trade, Slaves were obtained from mainland Africa and traded with the Middle East. The Anglican Cathedral is built on the site of a former slave market. Some of the holding cells still exist at the site.

The town also became a base for many European explorers, particularly the Portuguese, and colonisers from the late 1800s. David Livingstone used Stone Town as his base for preparing for his final expedition in 1866, a house, now bearing his name, was lent by Sultan Seyyid Said. Immigrant communities from Oman, Persia and India lived here. These were often engaged in trade or in the case of the Omanis were rulers of the island and its dependent territories.

Stone Town has been designated by UNESCO as a World Heritage Site.

It is also famous as the birthplace of Freddie Mercury, who used to be the lead singer of the band Queen.