Dr Allan Maca explores the legendary lost city of Xanadu in Inner Mongolia. Today very little remains of Kublai Khan's grand capital - a place that famous explorer, Marco Polo, described as one of the Marvels of the World. But now, with the help of satellite imagery and cutting-edge technology, we can finally uncover Xanadu's secrets, and bring this fabled city and its lavish palaces back to life.
Dr Allan Maca explores a newly discovered ancient megacity that 4000 years ago was one of the biggest on the planet. Its people created amazing Maya-like carvings like nothing ever found in China before. There's also grizzly evidence of human sacrifice on an unprecedented scale. This lost civilisation changes everything we thought we knew about the origins of China, but why, after 500 years, did they vanish? Allan and his team investigate ancient cataclysms to try to solve this great mystery.