Africa is a continent of magnificent treasures and cultures -- from the breathtaking stone architecture of 1,000-year-old ruins in South Africa to an advanced 16th century international university in Timbuktu. However, for centuries, many of these African wonders have been hidden from the world, lost to the ravages of time, nature and repressive governments. Join Harvard professor, Henry Louis Gates, on the journey from Zanzibar to Timbuktu, the Nile River Valley to Great Zimbabwe, the slave coast of Guinea to the medieval monasteries of Ethiopia in search of the lost wonders of the African world.—PBS