Pictish fort south of Stonehaven 'is Scotland's oldest'
A Pictish fort uncovered during an archaeological dig on the Aberdeenshire coast is believed to be Scotland's oldest.
BBC Scotland has learned that carbon dating tests have pinpointed the origin of the site on the sea stack back to the 3rd or 4th Century.
The original discovery by the University of Aberdeen team had been revealed in April.
The site, south of Stonehaven, is near the historic Dunnottar Castle.
Lead archaeologist Dr Gordon Noble described the find as "exceptional".
He said: "This is the most extreme archaeology I've ever done.
"The site can only be accessed using ropes at low tide and having never climbed before, it was quite hair-raising.
"But the challenge of getting to the top was soon forgotten as we began to make significant discoveries."
Aberdeenshire Council archaeologist Bruce Mann said: "The dates for this site are truly amazing, and hugely important for Scottish archaeology."
The sea stack is known as Dunnicaer.