In this episode Zeinab Badawi visits rarely seen historic sites and magnificent ruins in Mali and Mauritania in west Africa. We hear from Africans about how trans-Saharan trade, mainly in gold, meant that by about the 7th century rich kingdoms became established in West Africa. These eventually gave rise to three of the greatest empires on the continent, including the Mali Empire which began in the 13th century. Under armed guard, Zeinab visits the fabled city of Timbuktu, which was overrun by extremists in 2012. Mali’s ruler Mansa Musa was reputedly the wealthiest individual to have ever lived.