Chinese archaeologists have started the third of a series of excavations at the site of the famous terracotta army.

Archaeologists work at the excavation site of No. 1 pit of the Terra-cotta Warriors and Horses of Emperor Qin Shihuang, in Xi'an, capital of northwest China's Shaanxi Province, June 13, 2009. Archeologists began the third large-scale excavation of the Terra-cotta Warriors on June 13, China's fourth Cultural Heritage Day, after a halt of over 20 years. [Jiao Weiping/Xinhua]

They hope to find more clay figures and unravel some of the mysteries left behind by the "First Emperor of Qin."

The terracotta army is one of the greatest archeological finds of modern times.

The first formal excavation from 1978 to 1984 uncovered 1100 clay figures.

A second excavation, in 1985, lasted a year and was cut short for technical reasons.

This time the focus is on a 200-square meter patch in the the Number 1 pit, the largest of the three pits at the site.

Cao Wei, Vice Curator, Terracotta Army Museum, said, "It's hoped that we may find a clay figure that appears to be 'in command' of the huge underground army. The excavation will also test preservation technology that the museum has spent decades developing to keep the undiscovered terracotta figures intact and to retain their original colors."