Unguja Island, also referred to as Zanzibar, is the largest island in the Zanzibar archipelago. Stone Town is a historic centre of the island and a World Heritage site. Zanzibar is home to rare animal species like the Zanzibar red colobus, Zanzibar leopard and Zanzibar servaline genet.
House of Wonders - Built in 1883 for Barghash bin Said, second Sultan of Zanzibar, it is the largest and tallest building of Stone Town. It currently houses the Museum of History & Culture of Zanzibar & the Swahili Coast.

Hamamni Persian Baths - An historical building of Stone Town, built between 1870 and 1888 for Sultan Barghash bin Said for use as public baths, and maintained this function until 1920.

Old Fort of Zanzibar - The oldest building and the most important attraction of the Stone Town, this fort was built in late 17th century by the Omanis to defend the island from the Portuguese.

Zanzibar Butterfly Centre
- One of the largest butterfly enclosures in East Africa, with highly knowledgeable staff to help visitors through the various stages of a butterfly's life.

Old Dispensary
- It is also known as Ithnashiri Dispensary and owes its name to the fact that it served as a dispensary in the first half of the 20th century. It is a very finely decorated building wooden carved balconies and with stained glass decorations. The main structure is built with traditional Zanzibari coral rag and limestone, but covered with stucco adornments of European neo-classical taste.

Kizimkazi Mosque - One of the oldest Islamic buildings on the East African coast, the Kizimkazi Mosque is a mosque situated on the southern tip of the island of Zanzibar.

Microlithic tools found in the island suggest that it has been home to humans for at least 20,000 years. Persian traders used Zanzibar as a base for voyages between the Middle East, India, and Africa. The Persians built the first Zoroastrian fire temples and mosques in the Southern Hemisphere here. Vasco da Gama's visit in 1498 marked the beginning of European influence. In 1503 or 1504, Zanzibar became part of the Portuguese province of Arabia and Ethiopia. In 1698, Zanzibar fell under the control of the Sultanate of Oman.

Ivory was a major trade good. The group of islands  was famous worldwide for its cloves and other spices, and plantations were developed to grow them.

Malindi in Zanzibar City was the Swahili Coast's main port for the slave trade with the Middle East. In the mid-19th century, as many as 50,000 slaves passed annually through the port. In 1873 the British forced the Sultan to sign the Anglo-Zanzibari treaty, abolishing slavery, closing all slave markets and ensuring the protection of liberated slaves.

On 12 January 1964 Sultan Jamshid bin Abdullah was deposed during the Zanzibar Revolution. In April 1964, the republic merged with mainland Tanganyika.

Ethnic Swahili make up most of the population of Zanzibar, with a minority of Arabs and Indians.
Despite the heat of the summer, the island is often cooled by strong sea breezes particularly on the north and east coasts. It is warm throughout the year due to its proximity to the equator. Rains in November are characterised by brief showers. Longer rains normally occur in March, April, and May.