If you miss it now, there's no telling how long it will be before you'll get another opportunity to view Along the River During the Qingming Festival, the cream of Chinese fine art.

The work by Zhang Zeduan (1085-1145), perhaps the best-known ancient Chinese painting, will be unveiled to the public on Sept 8 in Beijing's Palace Museum, also known as the Forbidden City. It has not been shown in its entirety since 2005.

The 24.8-centimeter-wide, 5.29-meter-long scroll depicts a flourishing landscape in the onetime national capital, Bianjing, which is today's Kaifeng in Henan province. About 600 figures, 100 houses and 25 boats are shown in great detail in the painting.

An insurmountable peak of Chinese fine art history, the scroll is part of the feature exhibition The Precious Collection of the Stone Moat, which includes 283 ancient painting and calligraphy masterpieces to celebrate the museum's 90th anniversary of opening to the public.

According to Shan Jixiang, museum director, rules require that the painting must be temporarily retired for at least three years each time it is exhibited, with no one being allowed to touch it during this period.

The last display of the painting was in Japan in 2012, although only part of the painted scroll was unrolled then.

In 2010, the Shanghai Expo hoped to borrow the painting, but the museum refused the request, saying the artwork had not "rested enough". Instead, a magnified digital version of the painting was shown at the expo museum, which still attracts visitors who wait for hours to see it.

The Palace Museum, China's royal palace from 1420 to 1911, now houses 53,000 paintings and 75,000 calligraphy works. However, limited exhibition space and high safety standards have kept most of them locked in a warehouse for years.

In addition to Along the River During the Qingming Festival, other milestones of China's fine art history in the museum's catalogue include Spring Excursion, Letter to Boyuan and Five Oxen.

"It is unprecedented to put so many of the finest works together in such a luxury group," said Zeng Jun, head of the museum's calligraphy and painting department.

Though the exhibition is to be extended until Nov 8, these prominent displays will be replaced by other works on Oct 12.

"Perhaps the later exhibited pieces are lesser known by the public, but I can assure you they are equally supreme," Zeng said.

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