When you come to Hong Kong in the seventh month of the lunar calendar, you will see lots of colorful bamboo scaffolds located everywhere. The Chinese traditional Hungry Ghost Festival or Yu Lan is solemnly celebrated almost in every district during this month.

According to traditional belief, the seventh month on the Chinese lunar calendar is called Ghost Month. The gates of hell are sprung open to allow spirits spending the month visiting their families, feasting and roaming on earth.

In this month, Hong Kong people make efforts to appease these transient ghosts, while "feeding" ancestors. Grandfathers often warn children not to go out at nights. Residents burn joss paper offerings at street sides. The most popular offerings are Hell Bank Notes.

"August 10, which is the 15th day of lunar July this year, is called the official day of Yu Lan. Unlike Halloween in the West which is only celebrated for several days, Yu Lan can be celebrated for a whole month," said Xia Zhongjian, boss of the biggest joss paper offerings shop in Hong Kong.

A lot of bamboo scaffolds covered by decorative cloth and paper were set up for building the temporary theatres and memorial places.

"King of Hell, made by colorful paper and bamboo, is the signature figure of Yu Lan, I received more than 60 orders this year to make the King, and the tallest King will be around 8 meters high," Xia said.

Early this month, in a night we were invited to a Yu Lan Ritual in Hong Kong's Shau Kei Wan district by Paul Chan, the founder of a cultural oriented tourism agency "Walk in Hong Kong."

"People celebrate Yu Lan by organizing more than 100 'Yu Lan Rituals', and you can imagine it as a carnival involving both ghosts and human beings," said Paul Chan.

"It is a way of worshipping ancestors and expressing the filial piety in Chinese communities. The tradition has been handed down from generation to generation for more than several decades when the festival first came to Hong Kong in 1940s." Chan said.

Chan said that people perform Chinese traditional operas in temporary theatres to entertain ghosts and ancestors while the King of Hell, who acts like a "police officer", "monitoring" the whole ritual and "frightening" away bad evils.

At the ritual site, the King was standing in front of us gravely and in a dignified way, wearing colorful paper clothes and decorated with dozens of golden stickers.

According to normal ceremony of Yu Lan Rituals, the King often "cruises" streets in some districts to "supervise" general spirits. People who accompany him are expected to throw rice and beans to streets to help the King feed wandering spirits.

At the end, the King was burnt into ashes, and in this way he was sent back where he had been invited.