Palace Museum security staff keep visitors in order on Sunday. [Photo by Chen Xiaogen/China Daily]

On Friday, the 30,000 remaining tickets offered at on-site box offices were sold out within two hours, with long lines waiting outside the main gate.

Legal measures sought

Without law enforcement powers, the cultural relic protection units such as that at the Palace Museum have limited capability to punish unruly behavior, so more legal measures should be introduced, said experts.

Zhao Li, a lawyer from Jingshi law firm in Beijing, said: "We need to increase punishments for those who damage cultural relics. Perhaps they should even face a criminal penalty."

A number of incidents involving visitor misbehavior have raised public concerns while tarnishing Chinese tourists' reputation at home and abroad.

In early September, two lovers carved the names Zhang Tao and Liu Ya, as well as the shape of a heart, on a 300-year-old bronze vat at the Palace Museum.

The museum management team later reported the incident to Beijing police, who suggested that the couple turn themselves in. The couple have not yet stepped forward.

Shan, director of the Palace Museum, said the restoration of the carved bronze vat has been finished and security monitoring will be strengthened inside the museum.