But one feature of the sprawling necropolis, which A.R. Williams at National Geographic reports covers some 38 square miles, is almost beyond belief. The emperor, who died circa 210 B.C., was buried with an estimated 8,000 life-size and highly detailed warrior statues made of terra cotta. Now, a new theory suggests the statues were inspired by Greek art, and that ancient Greek sculptors may have made it to China more than 1,500 years before Marco Polo. Researchers have evidence to back it up; mitochondrial DNA shows Europeans interbred with the local population around the time the statues were made. The evidence will be detailed in a new documentary produced by National Geographic and the BBC.