With its pale-orange ramparts overlooking Forodhani Gardens and the ocean beyond, the fort was built by Omani Arabs when they seized the island from the Portuguese in 1698, and over the centuries it's had various uses, from prison to tennis club. Today the scale of the fortifications is still impressive, although there has been some modernisation inside, notably a line of souvenir shops and a pleasant cafe that turns into a bar in the evening.
Another modern feature is the open-air amphitheatre, used for local shows and major events, such as the Zanzibar International Film Festival and Busara; the tourist information desk at the fort entrance can advise on performance schedules. Also here (in one of the towers) is the Cultural Arts Gallery, connected to the Cultural Arts Centre Zanzibar, where you can meet local artists at work or join a hands-on course.