Time raiders - FT.com Tomb treasures from the Han dynasty go on show at the UK's Fitzwilliam Museum from May 5 Gold belt plaque, 2nd century BC Yinde Li was an archaeologist of 26 when the royal tomb of one of the Western Han dynasty kings of Chu - possibly Liu Dao (who reigned from 150BC-129BC) - was excavated on Beidongshan hill near Xuzhou, in the Chinese province of Jiangsu, in 1984. A farmer had contacted the authorities after stumbling across the hole through which grave robbers had entered and partially looted the site at some time in antiquity. Professor Li recalls slipping down a damp earth slide in near-total darkness. By the dim light of his torch, all he could make out was a mass of writhing serpentine forms the width of his wrist. I was terrified. I thought they were snakes," he laughs, his breath condensing in the chill air of the now denuded but hauntingly atmospheric tomb chamber. It was just like Indiana Jones. In fact, it was more like Indiana Jones than he initially realised - even though the snakes turned out to be tree roots dripping water down on to the tomb floor below. The great tomb gates had been closed with ingenious self-locking devices, and sealed with precisely hewn two-ton blocks of stone. Lining the tomb entrance passage, which had not been looted, were 224 well-preserved painted earthenware officials and guards with weapons in their hands or quivers on their backs. But what really makes this find so remarkable is that Beidongshan is the most complex of all the Han royal tombs so far excavated. It is, uniquely, a two-storey subterranean "building" cut into the rock of the hillside, 37m long and comprising 19 chambers, their intended functions - from armoury and reception hall to kitchens and ice store - revealed by the grave goods found in them. It can only be an imitation or approximation of the king's temporal palace. With the other royal tombs that cluster around the imperial family's home town of Pengcheng (modern Xuzhou) - the Han emperors wisely chose their close relatives to rule designated parts of their vast domain - the tomb's discovery opened the largest window yet on to the life and culture of the Han courts. Terracotta warriors These excavations are all the more compelling because the aristocracy and kings of earlier dynasties chose to be buried in large pits rather than in horizontal suites of palatial chambers. Moreover, no imperial mausoleum has ever been, or is likely to be, excavated - save for that of the Ming emperor Dingling, which was opened during the cultural revolution. As for the Han, the dynasty that reunified China in 206BC and ruled over it for more than 400 years, it could be argued that to understand them is to begin to understand modern China. That is one reason why, as the state authorities announced in Beijing in April, China has allowed more "first grade" cultural objects than ever before to be sent overseas for the landmark exhibition, The Search for Immortality: Tomb Treasures of Han China, which opens next week at the Fitzwilliam Museum in Cambridge. Finds from tombs of three Chu kings now in Xuzhou Museum will form the first part of this show. Most spectacular are the jade and gold objects from Shizishan, excavated in 1994-95 and the least disturbed of all the tombs. No expense was spared in ensuring the safety, comfort and amusement of this king in his after-life: the remains of his chef were found here. Also from this tomb came some of the Xuzhou Museum's star treasures. Jade was thought to protect the body from decay and corruption by demons, and the tomb yielded the only complete jade coffin in existence. And the finest of all surviving jade burial suits, this one crafted from an unusually high number of pieces - more than 4,000 - the individual articulated plaques of lustrous pale jade carved in a variety of shapes and sizes to hug the emperor's face and body, and sewn together with gold thread. This jade armature - no doubt analogous to the iron or lacquer armour worn by the living - with its silk-edged boots, gloves and mask, was intended as much to retain the king's "vital energy" as to keep out degrading evil spirits. The second king of Chu, if indeed it is he, was a surprisingly tall man - the suit is 175cm long. Jade burial suit, 2nd century BC The works of art are even more beguiling. A jade ornament carved in high relief as an end piece for the king's pillow takes the form of a lion or monster with curling horns that stares out of great bulbous eyes. An exquisitely detailed gold belt plaque writhes with horse-like animals attacked by ferocious wolves and bears - a riot of claw and fang bordered by the heads and beaks of birds. This taste for the exotic - and for antiquities - showed, too, in the unlooted tomb of Zhao Mo, the second king of Nanyue (who reigned from 137BC-122BC), a vassal state on the southern periphery of the Han Empire that had its capital near modern-day Guangzhou, the gateway to the rich trade routes of the South China Sea. It was in 1983 that this small but elaborately decorated tomb was discovered during construction work - and the army guards still based at the site of the tomb and nearby museum show that it is considered one of the most important finds of modern archaeology. Inside, the king's coffin was a silver-lobed vessel from Parthian Persia that was used as a pill box, while a jade dragon with a gold tiger-headed hook, one of many surviving items from the earlier Warring States period, was found on his right shoulder. Jade ornament with animal mask, 2nd century BC Again, the museum is generously offering up its greatest treasures - including the king's gold seal and the earliest of all known jade suits, this one fastened with red silk. Zhao Mo flouted the authority of the Han and styled himself emperor, and arranged an appropriately grand burial. In front of his coffin was another tour de force, a tubular jade cup supported by gold-headed silver dragons soaring up from the rim of a bronze basin. Drinking dew and jade powder from a jade cup was believed to confer longevity, and this vessel - like many other objects on show - was probably used in the royal palace during the king's lifetime. This will be the first time that material from the tombs of the kings of Chu and Nanyue is exhibited together. It is a compelling tale not so much of death but of life and the quest for immortality, as told through the real and the symbolic, the everyday and the supernatural. The panoply of life in a western Han court is here - from the functionaries to the musicians and long-sleeved dancers, the chefs, grooms and other servants. We find the games and musical instruments played, ritual vessels, utensils for writing, bathing and cooking, and the tools for fishing, carpentry and printing silk ... There is even a stone privy - there were three at Beidongshan. Indiana Jones might not have expected that. "The Search for Immortality: Tomb Treasures from Han China," Fitzwilliam Museum, Cambridge, May 5-November 11, www.fitzmuseum.cam.ac.uk