Fredrik T. Hiebert is an archaeologist and explorer who has traced ancient trade routes overland and across the seas for more than 20 years. He has led excavations at ancient Silk Road sites across Asia, from Egypt to Mongolia and rediscovered the lost "Bactrian Gold" in Afghanistan in 2004. His excavations at a 4,000-year-old Silk Road city in Turkmenistan made headlines around the world. Hiebert joined the National Geographic Society in 2003. He is the author of "The Origins of Oasis Civilization in Central Asia" (1994), "A Central Asian Village at the Dawn of Civilization" (2006) and "Qal'a...