The archaeologists record their finds on the Hertfordshire site
A Bronze Age henge has been discovered on land near Letchworth.
Archaeologists have found a circular area about 50 metres wide surrounded by a bank at Stapleton's Field in Norton.
North Herts Archaeology Officer, Keith Fitzpatrick-Matthews said: "Henges are quite rare with only 60 known in the UK, so this is a significant find.
"It's interesting as the only other henge known locally is on the Weston Hills, which is visible from the site we are working on."
Keith Fitzpatrick-Matthews, leading the team working on the site, revealed how the henge which dates back to between 3000 and 2000 BC was discovered:
Working on trench one at the site
"Ariel photographs of the area showed this rather extensive ring of chalk.
"There's nothing visible at ground level so we decided to put a trench through it.
"Having done that we found the chalk bank just survives underneath the plough soil and we have massive ditches inside and out."
The archaeologists are able to date the henge because of pottery they found which is associated with the Bronze Age.
"Grooved ware products were found, which dates the henge back to the third millennium BC," explained Keith Fitzpatrick-Matthews.
A circular earthen bank and ditch enclosing an area of varying diameter.
The earth used to build the banks was taken from the ditches and the central area flattened.
Henges are only known to occur in Britain and Northern Ireland. They are commonly found in 'groups', each separated by hundreds of miles.
There are various theories as to the purpose of a henge. Some experts believe henges were used as a defence, while others think they were meeting places for rituals.
There is an open invitation on Saturday 28 August 2010 at 2pm for members of the public to visit the site and view items on display.
Stapleton's Field lies between Church Lane, in the centre of Norton and the A1(M) motorway.