The earliest evidence of cannabis being used to get people high has been uncovered by scientists in western China dating back 2,500 years.
The first drug den is a mountain tomb associated with the Zoroastrian religion.
Traces of burnt seeds found in wooden braziers at a mountain burial site have been analysed and revealed to be cannabis - with high levels of THC, the compound that produces the drug’s feelings of euphoria.
As the seeds were found in wooden braziers, scientists believe the cannabis was being used for ritual and religious activity.
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The earliest evidence of cannabis being used to get people high has been uncovered by scientists in western China dating back 2,500 years. The first drug den is a mountain tomb associated with the Zoroastrian religion
And because the cannabis was burnt in an enclosed space - inside a tomb of elite members of the community- it is thought it was ‘wicked weed’ used by mourners to get high, according to reports on the discovery in the journal Science Advances.
Cannabis plants - also known as hemp - have been used to make paper, rope, cloth and oil for around 4,000 years.
There have even been claims cannabis was burnt for drug effects 5,000 years ago. But these older traces had signs of low THC content.
So it cannot be certain that they were used by people to get high.
But the finding in China is the earliest yet-discovered sign the plant was being used as a recreational drug.
Archaeologists found ten wooden braziers containing stones with obvious traces of burning in eight tombs at the Jirzankal Cemetery in the Pamirs mountains of, western China.
The tomb site dates back to 500 BC. Written records show that around this time, civilisations were taking advantage of the mind-altering effects of cannabis - but this is the first concrete proof of its use.
In 440BC, the Greek historian Herodotus wrote that the nomadic Scythians, who controlled vast areas from Siberia to Eastern Europe, made tents and heated rocks in order to inhale hemp vapours that made them ‘shout for joy’.
The researchers, from Germany’s Max Planck Institute are engaged in a wider project to trace how the cannabis plant, which grows wild in Central Asia, spread along the Silk Road and became a common recreational drug.
The Silk Road is better known as being the route that took spices, grains, crops and food from the East to the west, not to mention silk.
Academic Robert Spengler, of the Max Planck Institute speaking of the discovery said: ‘Recent studies have shown that apples, pistachios, walnuts are among the crops that actually originated on these trade routes through Central Asia, and I think with this new study we can now actually place Cannabis in that list as well as being one of these crops