Kwale Island or Kwale Island Marine Reserve is a protected, seasonally inhabited island in the Pemba Channel under the Tanga Marine Reserves (TMRS) with the IUCN category II located inside Kwale, Mkinga District in Tanga. The coral island, located approximately a kilometer offshore in Manza Bay, 86.2% of the 12.128 km² of Kwale Island, is covered with mangroves. 

Kwale Island was historically inhabited by tribe of Wadiko, people living along the beaches. Due to frequent attacks by Masai soldiers, Wadigo from Mwandusi village retreated and later settled in Kwale Island, where they were safe as Masai were afraid to cross into the Island. However, they were forced to go back to the mainland due lack of fresh water and family expansion. Most settled in Kwale village. This Island was also used during the first and second World wars as fortress.

Today, a dense vegetation of trees, including large baobabs, mangroves, and dense thorn bushes completely covers the island. Since there is no legal protection, people are chopping down the forests for fire wood. Additionally, the island has produced some Swahili ware pottery fragments from the Middle Ages, indicating that it once belonged to the Swahili states. The island has historically been deserted since.

What to See: Ruins, Mangroves, Coral Reefs, and Birds