A path traversed by caravans laden with silk, spices and much more besides, the old Silk Road influenced trade, religions, cultures and economies across Europe, Asia and far beyond. In his latest book, Riaz Dean blends the best of this region's history and geography with ancient cartography to solve a 2,000-year-old riddle that has perplexed scholars for centuries: Where was the Stone Tower that the great geographer Claudius Ptolemy had written about? This highly significant but now-lost landmark represented the midpoint and thumping heart of the Silk Road, as merchant caravans plied their wares between the Occident and the Orient. From the significance of the Heavenly Horses to the intrigues of geopolitics and war between clans and kingdoms, Dean brings to life the legendary Silk Road even as his evocative narrative and meticulous research pinpoints the Stone Tower's probable location somewhere by the so-called Roof of the World.