BEIJING (TIP): An hour before the Forbidden City opened to visitors one recent morning, the stone courtyard just south of the ancient imperial palace was abuzz. Within the vermilion walls, the usual mix of uniformed palace workers, tour guides and tourists milled about beneath a pale blue sky. Loudspeakers blared a recording about ticketing policies.

But at the center of it all was an atypical sight: a phalanx of more than 1,000 people, flanked by palace workers whose job was to keep the ranks in line. Unlike most visitors, this small army had come with only one goal: to see “Along the River During the Qingming Festival,” an early 12th-century painted scroll considered so iconic that it is often called “China‘s Mona Lisa.”

Since an exhibition celebrating the 90th anniversary of the Palace Museum opened in early September, people have been waiting for up to 10 hours to see this 17-foot-long masterpiece attributed to the painter Zhang Zeduan, an intricate ink-on-silk tableau of life in the Northern Song dynasty capital, Kaifeng. The best-known painting in the museum’s vast collection, it has been shown in public only a few times, in Beijing most recently in 2005 for the museum’s 80th anniversary.

The fanatical interest in the work coincides with a concerted push by the Chinese government to encourage interest in traditional culture and values, as a way of emphasizing its links to a history that goes back thousands of years.