The remains of what is believed to be one of Scotland's earliest homes have been uncovered during construction works for the new Forth crossing.The site dates from the Mesolithic period, about 10,000 years ago.
Archaeological excavation works have been taking place in a field at Echline in South Queensferry in preparation for the Forth Replacement Crossing.
A large oval pit nearly 7m in length is all that remains of the dwelling, along with hearths, flint and arrowheads.
'First settlers' Rod McCullagh, a senior archaeologist at Historic Scotland, said: "This discovery and, especially the information from the laboratory analyses adds valuable information to our understanding of a small but growing list of buildings erected by Scotland's first settlers after the last glaciation, 10,000 years ago.
"The radiocarbon dates that have been taken from this site show it to be the oldest of its type found in Scotland which adds to its significance."
The remains feature a number of postholes which would have held wooden posts to support the walls and roof, probably covered with turf.Several internal fireplace hearths were also identified and more than 1,000 flint artefacts were found, including materials which would have been used as tools and arrowheads.
Other discoveries included large quantities of charred hazelnut shells, suggesting they were an important source of food for the occupants of the house.
Archaeologists believe the dwelling would have been occupied on a seasonal basis, probably during the winter months, rather than all year round.
Ed Bailey, project manager for Headland Archaeology, the company that carried out the excavation works, said: "The discovery of this previously unknown and rare type of site has provided us with a unique opportunity to further develop our understanding of how early prehistoric people lived along the Forth.
"Specialist analysis of archaeological and palaeoenvironmental evidence recovered in the field is ongoing. This will allow us to put the pieces together and build a detailed picture of Mesolithic lifestyle."
Transport Minister Keith Brown said: "This ancient dwelling, which was unearthed as part of the routine investigations undertaken prior to construction works, is an important and exciting discovery.
"We now have vital records of the findings which we will be able to share to help inform our understanding of a period in Scotland's ancient history."