An intact chicken egg estimated to be around 1,700 years old is believed to be the only of its type in the world, after scientists found it still had liquid inside.

It was discovered during a dig in Aylesbury in Buckinghamshire between 2007 and 2016, with researchers saying at the time that it was a “genuinely unique discovery”.

During the course of the excavation, archaeologists broke three other eggs which released a “potent stench”, but a fourth egg remained intact.

Experts from Oxford Archaeology think the waterlogged pit may have been used as a sort of Roman wishing well.

Now, a micro scan has found that the egg still contained the yolk and egg white and is believed to be the only intact egg from the period.