Begin with a trip to Prison Island, where giant tortoises have been residing since 1919. It's a great spot for snorkeling and sunbathing. The island also once functioned as a quarantine station before the British constructed the Stone Town prison. Next, explore Stone Town, a UNESCO World Heritage site, and discover its historic landmarks, such as the Old Market, House of Wonders, Tippu Tip House, Old Fort, and the Former Slave Market (optional).