But real-life archeologists have found it.
The grave of Cao (AD 155-220), the founder of Wei Kingdom - the strongest and most prosperous state during the Three Kingdoms period (AD 208-280), was discovered in Anyang City in central China's Henan Province, archeologists announced yesterday in Beijing.
According to Chen Ailan, director of the Henan cultural heritage administration, the discovered tomb, close to the former site of Wei's capital Luoyang, was confirmed as Cao's.
The 740-square-meter tomb, a size appropriate for a king, was confirmed to have been built at the time of Wei.
A stone tablet discovered at the scene said it belonged to the king of Wei, and the remains in the tomb were determined to be of a man in his 60s. Cao died at 65.
Two women's bodies were also discovered in the tomb.
Cao is remembered for his outstanding military and political talents - "capable minister in peaceful times, righteous hero in chaotic times," as one scholar put it.
He is also known for his poems - some included in China's middle school textbooks.
Characters based on Cao appear in major traditional Chinese operas, including Peking Opera and Sichuan Opera. A Chinese proverb, "speak of Cao Cao and he appears," is the equivalent of "speak of the devil" in English.
In the well-known historical fiction, "The Romance of Three Kingdoms," a fictionalized Cao says, "Better for me to wrong the world than for the world to wrong me."
The book secured his position as a villain in Chinese literature.
A famous tale said Cao was buried secretly and protected by 72 fake tombs to prevent raiders' invasion.
But while the location of his tomb was lost to history, it used to be clear and was visited by many well known historic figures, including the Tang Dynasty Emperor Li Shimin (AD 618-907).
No luxury decorations were found in the tomb, but more than 250 weapons, pieces of armor, pottery and other articles were confirmed as Cao's everyday belongings.