CHONGQING, China — On a sweltering morning last month, a white-haired guide trudged up a muddy path, leading a group of scholars toward a bamboo grove on the outskirts of this western Chinese city. The site, he said, was where a large portion of China’s imperial treasures were once hidden inside several big wooden sheds.

“They were stored right about here,” Hu Changjian, a local museum official, said of the artifacts, an unparalleled collection of more than a million objects from the Forbidden City in Beijing, including fine paintings, calligraphy, jade and porcelain dating back centuries. He added, “We think they dug caves in the hills behind us to store some of the treasures.”

Photographers and documentary filmmakers traveling with the group of scholars recorded the scene, as the scholars, clutching notepads, scampered up a hill in search of caves.

The scholars, from mainland China and Taiwan, were taking part in an extraordinary two-week research project, retracing the routes taken by the imperial treasures in the 1930s and 1940s, when they were being safeguarded from the ravages of civil war and Japanese aggression, not to mention floods, bandits and warlords.