It covers an area the size of Cambridge but so far only a tiny proportion of the site of the First Emperor of China’s underground palace for the afterlife has been excavated.

Now Chinese archaeologists have used computerised imagery to complete a 3-D reconstruction of the giant tomb that lies 30 metres beneath a mound, with the Qinling mountains in the background.

The dramatic imagery has been made available to The Times by the historian John Man, before he publishes pictures and a detailed description of it in his book The Terracotta Army: China’s First Emperor and the Birth of a Nation next month. The reconstruction of the tomb has been put together by a team led by Duan Quingbo, of the Shaanxi Institute of Archaeology, and it is being made public as some of the greatest finds at the excavation site — including figures from the famous Terracotta Army — are due to go on display at the British Museum.

The life-size figures, including bureaucrats, musicians and acrobats connected to the First Emperor’s civilian administration, will go on display on September 13 — making it the largest show at the British Museum since its Tutankhamun exhibition had visitors queueing around the block in 1972.

The treasures include some of the 1,000 figures that have been excavated so far. An estimated 7,000 more are believed to be underground.

A description of the palace dating from 89BC — about 100 years after its construction — hints at fabulous wealth, with models of palaces and pavilions, vessels and precious stones. Mr Man said that the reconstruction came about after archaeologists probed down from the surface, hitting stone and rammed earth walls. “If you join the dots, they look like an underground, four-sided palace of some considerable size.”

Nobody knows what sort of roof it had. If it was wooden, it would have collapsed long ago, he said.

About 3,000 families have been moved out of the area, near Xian in the Shaanxi province, in preparation for a more detailed survey around the tomb, although the excavations will continue for many decades.

The tomb is unparalleled in world archaeology. The Terracotta Army was discovered by chance in 1974 and the site that it guards has continued to be dug since then, with many new treasures coming to light.

It was created on the orders of Qin Shihuang, the First Emperor of the Qin Dynasty, and the man who created the state of China 2,000 years ago. He united the various warring states into one political body in 221BC, making what is now the oldest surviving political entity in the world. He presided over the standardisation of coinage and weights and measures as well as script, which represented a huge step towards the development of China as a nation.

Jane Portal, the British Museum’s curator, said that the reconstruction of the tomb brought the structure to life, and would be included as part of the exhibition’s audio-visual display.

The exhibition, sponsored by the financial services firm Morgan Stanley, will include more than 120 objects from China. Along with about a dozen examples of the terracotta warriors, there will be life-like bronze geese, swans and cranes that are thought to have danced to the music made by the terracotta musicians — for the Emperor’s entertainment.

The Terracotta Army: China’s First Emperor and the Birth of a Nation runs from September 13 until April 6. To book telephone 020-7323 8181.

Imposing figures

56

square miles — size of the Xian site

25,000

square metres — the area of pits containing warriors, discovered by chance in 1974 by a peasant drilling a well

36 years

The time it took to build, from 246BC to 210BC

700,000

The estimated number of people, probably forced labour, involved in the construction

13

The age at which Ying Zheng became the King of Qin in 246BC

Source: Times Database

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