WORKERS revamping the Grassmarket unearthed more than they bargained for when they dug up sections of a wall built to guard the Capital centuries ago.
The remains are part of the Flodden Wall, built around the city in the 16th century in response to a threatened English invasion.
The section of wall, which lies at the King's Stables Road end of the Grassmarket, was discovered as work continues on the 5.1 million revamp of the area.
The uncovered section, which measures about 1m x 5m, has been catalogued and photographed by archaeologists and then sealed up, as it is below the foundations for a new road.
The wall's exact location will be marked with brass plates, similar to those in place along the Royal Mile which note the locations of historically significant buildings such as the Old Tolbooth Prison in Parliament Square.
The conservation work has been carried out over the last two days so there will be minimal delays to the ongoing work.
The latest Flodden Wall discovery is opposite one of the best-preserved sections of the wall at the Vennel.
City archeologist John Lawson said the discovery will help people learn more about Edinburgh's colourful history. "This section of the wall is exactly where we expected it to be but it is still an exciting find," he said.
"From a residents and traders point of view it is good that we have been able to get in and record what we need to without delaying the Grassmarket works.
"There have been quite a lot of services, such as gas and sewage pipes, put through the wall over the years, but from what we have seen it is still in a reasonable condition.
"We have closed it up with a protective seal as the section actually forms the foundations of a new section of road, but the option is there to open it up again at a later point.
"But I am realistic about that, given how busy that road is.
"We didn't expect to find a great deal from the Grassmarket work but it is proving to be quite rewarding."
Bill Cowan, spokesman for the Old Town Association, said of the latest find: "This is a great discovery, I think it is important that we mark the location of the wall and it would be nice to see a plaque put up to tell people a little bit more about the wall.
"On the other side of things, it is also welcome that the work will not hold up construction."
Other sections of the Flodden wall that are still in good condition can be found at the corner of the Pleasance and Drummond Street, where it originally enclosed the Blackfriar's Monastery.
In April, council archaeologists unearthed evidence in the Grassmarket that revealed humans were in the area 3000 years earlier than was previously thought.
The surprise find puts the earliest known civilisation in the area as far back as the Middle Bronze Age, or around 1500 to 1300BC.
Until then, archaeologists thought the Grassmarket was first used in the 14th century. The find is the earliest piece of excavated material unearthed in the Capital, predating material from around 850BC found during digs at Edinburgh Castle in the 1980s.