Joe Wilkinson takes us on a tour of the island of Zanzibar, where the slave trade continued long after the British abolished it.

Mention Zanzibar and most people will think of an Indian Ocean paradise, perfect for honeymooners, relaxing on the popular pristine white north-eastern beaches of Bwejuu and Paje, swimming with dolphins in crystal-clear warm Indian Ocean water and gazing at spectacular sunsets. And while this undoubtedly contributes to Zanzibar’s charm, there is considerably more to Zanzibar than tourism. History permeates every corner of the island and for history enthusiasts there is much to explore – more than one would expect for such a small island (2,460sq km) – with most of this island’s history coming down to two things – slavery and spices...