Within the 3,899 hectares of property zone, its key elements included nine imperial mausoleums, 271 subordinate tombs, 32 flood control work sites, and a 5.03-hectare architectural complex site to the north, whose nature remains subject to debate but most scholars agree that it was used for rituals.

"The combination of artificial and natural elements creates a unique and majestic landscape at the tombs," says Chen Tongbin, honorary director of the Institute of Architectural History, affiliated to the China Architecture Design and Research Group.

Chen is a main drafter of the bidding document seeking World Heritage site status. Visiting the site numerous times, she is still amazed at the breathtaking sunset vista that unrolls in front of her eyes.

"It's hard to grow crops on the landscape of proluvial fan," she explains. "The land is not suitable for massive construction. The site has thus not been much disturbed other than through natural erosion. Its integrity leaves us with a credible source to know history."