"Pig's Blood Applied to the Red Walls of the Forbidden City"... The Truth Behind the Evil Spirit Rumors

Pig's Blood Used as Protective Coating for Wood
Architectural Technique Dating Back to the Ming Dynasty
Rumors of Evil Spirits Stem from Palace Folklore

It has been revealed that pig's blood was used on the red walls of the Forbidden City in China, a UNESCO World Cultural Heritage site. This was not for exorcising evil spirits, but to protect the wooden structures.

The view of the Forbidden City in China.

On April 26, the South China Morning Post (SCMP) in Hong Kong reported this fact, citing the book "Sitting Under the Roof of the Forbidden City: Answering 50 Questions About the Forbidden City" by ancient architecture expert Zhou Qian, who has studied the site for 20 years. In China, there is a rumor that as much as 600,000 tons of pig's blood is applied to the Forbidden City every year to ward off evil spirits, and that this is the reason the red walls remain vibrant.

Rumors surrounding pig's blood are tied to old folk tales about the Forbidden City. In the past, many officials, royals, and servants reportedly lost their lives unjustly, leading to widespread stories about ghosts appearing in the palace, and much speculation about the true nature of the red walls.

For example, on a stormy summer day in 1992, numerous visitors claimed to have seen a group of palace maids passing in front of the red wall. Experts explained this as an optical illusion caused by the iron oxide contained in the wall paint, but the public was not easily convinced. There is also a ghost story linked to a well in one corner of the palace called "Zhenfeijing." In 1900, under orders from Empress Dowager Cixi, Concubine Zhen reportedly died after falling into this well, leading to rumors of a woman emerging from it or the sound of weeping being heard. Today, the well is said to be covered by an iron grate.

The fact that the Forbidden City closes daily at 5 p.m. has also been surrounded by rumors that visitors are sent out before ghosts appear. However, officials at the Forbidden City have explained, "Staff need time to inspect the exhibits after visitors leave."

In reality, the use of pig's blood is far removed from these ghost stories. In his book, Zhou explains, "The mixture applied to wooden structures or the exterior of walls is called the 'Dijiang layer,' and it actually contains pig's blood." He clarified, "It is not for exorcising evil spirits but is used as an adhesive."

Pig's blood is mixed with brick powder, tung oil, and hemp to make a coating agent. When applied to wood surfaces, it protects the wood from sunlight, rain, and insects. Workers then add red paint or decorative drawings on top of this coating. Zhou explained, "Thanks to pig's blood, the coating layer adheres more firmly and lasts longer," describing it as a scientific technique devised by craftsmen since the Ming Dynasty.

Meanwhile, the Forbidden City served as the residence of emperors and the center of Chinese political power for over 500 years, from 1420 to the early 20th century. It was designated a UNESCO World Cultural Heritage site in 1987 and is considered the largest imperial palace complex in the world. Last year, it drew 18 million visitors, making it China's most popular tourist attraction, up from 17.6 million the previous year.

This content was produced with the assistance of AI translation services.