A remote Iron Age fort built by the Picts as a look out post on top of a 20-foot-high sea stack has been uncovered on the coast of Scotland. Archaeologists believe the stronghold, which would have been cut off from the land at high tide, may have been one of a number that lined the east coast of Scotland. The fort, which was found on top of the Dunnicaer sea stack close to Stonehaven, Aberdeenshire, appears to have been built with stone imported from elsewhere in the country. The small fort was discovered on top of Dunnicaer sea stack (shown above) and would have given the inhabitants a strong defensive position, although resupplying the fort up the cliff faces would have been hard . Stones used to construct the walls were also engraved with Pictish designs of fish and disks with broken spears through them. Dr Gordon Noble, an archaeologist at Aberdeen University who led the excavation, said the site was so remote it could only be accessed by climbing up the cliff face with ropes. The Picts were a group of tribes who lived north of the Forth and Clyde during the Late Iron Age and Early Medieval period. By the late 200s AD the Picts had overrun the northern frontier of the Roman empire more than once. Mel Gibson's blue face . paint in Braveheart is a nod to the Pictish tradition of body-paint - . but the real Picts fought stark naked, and there are records of them . doing so up until the 5th Century. The Roman name for the people - Picti - means 'painted people'. It's not known what they called themselves. The habit of fighting naked, especially in the cold Scottish climate, didn't harm the tribe's reputation for ferocity.  Picts were . one of the reasons even heavily armoured Roman legions could not conquer . the area. He said it appeared that despite its position, the fort had been lived in for extended periods and so must have been an important building. Dr Noble said it was possible the fort had been built there to help the Pictish tribes living there dominate the sea in the area. He said it was possible the fort, which is thought to date from the 5th to 6th century, could also have been a precursor to Dunnottar Castle, a medieval fortress built on the rocks of a headland less than quarter of a mile away. Dr Noble said: ‘It is possible that there was a series of forts along the coast. 'The Picts were known as sea raiders and forts like this may have helped cement that naval power. ‘It is quite an impressive site. It was pretty hairy climb to get up there and at high tide it is completely cut off. Resupplying the fort when it was inhabited would have been a challenge.’ The Picts were a group of tribes that lived in eastern and northern Scotland. Although best known for the carved stones and jewellery they left behind, it is thought that they were farmers but also engaged in sea raids. The archaeologists discovered the fort on Dunnicaer after following up reports that Pictish stones had been found there when some local youths climbed up the sea stack. Dr Noble said: ‘Being youths, they did what youths do and threw them down into the sea. ‘One of them returned later to collect one of the stones and since then a few others have been found. They had rough designs carved into them.’ When Dr Noble and his team from the Northern Picts project conducted a five day excavation on the top of the site, they uncovered the remains of what appears to be a rampart wall. They also found post holes and the remains of a hearth that appears to have been within a house built inside the fort. They even found charcoal still in the stone fire place. Mr Noble said there may have been a settlement built on the land behind the fort, although as the Picts largely built their homes from wood, it would be hard to find many remains. In order to reach the site, the team had to employ the services of professional rock climber Duncan Patterson, who climbed up the sea stack and put ropes in place. The archaeologists found the remains of a stone wall that would have formed part of the Iron Age fort . Some of the stones used to build the walls of the fort (like the one above) had rough Pictish carvings on them . The sea stack is only accessible at low tide and still requires a rock climb up the cliff face to reach the summit . This stone hearth, with the black charcoal dust still evident at the bottom of the picture, was uncovered by the team. It suggests the fort had been inhabited for relatively long periods, according to Dr Gordon Noble . Mr Noble said that at the time when the fort had been inhabited it may have had a wooden bridge across to the stack from the land otherwise it would have been very hard to access. He said: ‘The stone is not local, so it was quarried elsewhere and taken to build the fort and carved. ‘As for access, it is possible an easier route was present on the landward side and has now eroded, but certainly a timber access of some kind is well within their capabilities.’ The team now hope to examine some of the charcoal and other artifacts they found at the site in the hope of getting a better understanding of who lived there. The Dunnicaer sea stack sits just off the east coast of Scotland close to Stonehaven in Aberdeenshire . The researchers also found evidence for post holes (above) that were used in the fort ramparts during the dig . Archaeologists had to set up ropes to reach the sea stack after a professional climber scaled the rock face . Dunnicaer sea stack ( on the far left of the picture above) is just quarter of a mile from Dunnottar Castle (right)
Ancient fort was built on 20-foot sea stack near Stonehaven, Aberdeenshire .
Archaeologists needed to use ropes to reach the summit for the excavation .
They found remains of stone walls, ramparts and a charcoal filled fireplace .
Experts believe it may have been one of a line of forts along Scottish coast .