A flush toilet dating back to before the birth of Christ has been found in an archaeological dig in China.
The toilet was unearthed at a palace in Yueyang city in Xi'an, Shaanxi province.
Thought to have been used by a high-ranking individual, it likely dates from 2,400 years ago, during the 'Warring States' period of Chinese history, or possibly to the first emperor of the Han dynasty 2,200 years ago.
Most of us imagine that flush toilets are a modern invention, but toilets that are kept clean with water date back to the Neolithic period, from between 10,000BC and 2,000BC. In Britain, a flush toilet that used a stream to carry away human waste was found at a Bronze Age site in Skara Brae in Orkney.
Archaeologists now hope to test the Yueyang toilet for faeces in the hope of learning more about the people of the era.
The researchers have suggested it was manually filled by serving staff before the high-ranking individual sat on it.
Liu Rui, a researcher at the Institute of Archaeology at the Chinese Academy of Social Sciences, told China Daily: "It is the first and only flush toilet to ever be unearthed in China. Everybody at the site was surprised, and then we all burst into laughter."
A pipe led from the toilet to a pit outdoors.
The upper half of the toilet has not yet been found, so researchers cannot confirm whether it was used in a sitting or standing position.
Liu said: "The flush toilet is concrete proof of the importance the ancient Chinese attached to sanitation.
"Besides all written records, we can learn more about social reforms and systems of the kingdom by digging deeper into ancient palaces."
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