Experts have confirmed they have unearthed a Neolithic henge... in Iwade.

The 6,000-year-old prehistoric monument, which is 30m in diameter and consists of a pair of ringed ditches, is said to be "as rare as hen's teeth".

Its origins were finally laid bare after months of excavations at a site off Sheppey Way, which is being prepared for a 400-home development.

Dr Paul Wilkinson, whose team SWAT Archaeology made the discovery, said: "There are not many of these sites around.

"Its purpose is not known, but it may be that the monument was reused as an enclosure for stock management at this time or could formally have been used as a 'sacred way' leading to the Neolithic henge."

The outer ring at the Iwade site is thought to be Neolithic, its possible purpose being a ceremonial meeting place.

The unbroken inner circle is believed to stem from the Bronze Age and may have been used as a funerary monument to commemorate a dead person or group.

Near the rings, a second similar, but smaller monument, was also found by archaeologists.

Dr Wilkinson said all the archaeology has now been removed from the site.

Photos, drawings and artefacts collected during the dig will be examined to determine more about the land's history and how its inhabitants lived at the time.

With the dig complete, Kent County Council has signed the site over to developers, Persimmon, for work on the housing scheme - known as Iwade Meads - to begin.

Dr Wilkinson said although discoveries such as the one in Iwade are rare, a Neolithic henge was uncovered in nearby Sonora Fields last year, while in Hollingbourne, an early Iron Age site was revealed.

He said: "As more housing developments take place, we're discovering more of the prehistoric landscape. Large areas are being stripped of soil and exposing the archaeology."

Cllr Ben Stokes, representative for Iwade and Lower Halstow ward, said: "It's excellent news that the origins of this site have finally been revealed.

"We look forward to hearing more about the henge's fascinating history as the weeks and months progress."