Necropolis

The Terracotta Army is part of a much larger necropolis. Ground-penetrating radar and core sampling have measured the area to be approximately 98 square kilometers (38 square miles).

The necropolis was constructed as a microcosm of the emperor's imperial palace or compound and covers a large area around the tomb mound of the first emperor. The earthen tomb mound is located at the foot of Mount Li and built in a pyramidal shape, and is surrounded by two solidly built rammed earth walls with gateway entrances. The necropolis consists of several offices, halls, stables, other structures as well as an imperial park placed around the tomb mound.

The warriors stand guard to the east of the tomb. Up to 5 metres (16 ft) of reddish, sandy soil had accumulated over the site in the two millennia following its construction, but archaeologists found evidence of earlier disturbances at the site. During the excavations near the Mount Li burial mound, archaeologists found several graves dating from the eighteenth and nineteenth centuries, where diggers had apparently struck terracotta fragments. These were discarded as worthless and used along with soil to back fill the excavations.

Tomb

The tomb appears to be a hermetically sealed space roughly the size of a football pitch (c. 100 × 75 m). The tomb remains unopened, possibly due to concerns over the preservation of its artifacts. For example, after the excavation of the terracotta warriors, the painted surface present on some terracotta figures began to flake and fade. The lacquer covering the paint can curl in fifteen seconds once exposed to Xi'an's dry air and can flake off in just four minutes. 

Excavation site

Pit 1

Pit 1, which is 230 metres (750 ft) long and 62 metres (203 ft) wide, contains the main army of more than 6,000 figures. Pit 1 has eleven corridors, most more than 3 metres (10 ft) wide and paved with small bricks with a wooden ceiling supported by large beams and posts. This design was also used for the tombs of nobles and would have resembled palace hallways when built. The wooden ceilings were covered with reed mats and layers of clay for waterproofing, and then mounded with more soil raising them about 2 to 3 metres (6 ft 7 in to 9 ft 10 in) above the surrounding ground level when completed.

Others

Pit 2 has cavalry and infantry units as well as war chariots and is thought to represent a military guard. Pit 3 is the command post, with high-ranking officers and a war chariot. Pit 4 is empty, perhaps left unfinished by its builders.

Some of the figures in Pits 1 and 2 show fire damage, while remains of burnt ceiling rafters have also been found. These, together with the missing weapons, have been taken as evidence of the reported looting by Xiang Yu and the subsequent burning of the site, which is thought to have caused the roof to collapse and crush the army figures below. The terracotta figures currently on display have been restored from the fragments.

Other pits that formed the necropolis have also been excavated. These pits lie within and outside the walls surrounding the tomb mound. They variously contain bronze carriages, terracotta figures of entertainers such as acrobats and strongmen, officials, stone armour suits, burial sites of horses, rare animals and labourers, as well as bronze cranes and ducks set in an underground park.