The finds have been made on the Crubenmore to Kincraig stretch of the trunk road near Kingussie.
Archaeologists have been working on the route of the A9 to check for previously hidden ancient structures and other significant remnants from the past.
The latest discoveries emerged after archaeologist investigated “several interesting anomalies” identified in a geophysical survey.
The area was of heightened interest to archaeologists given its close proximity to a prehistoric souterrain called Raitt’s Cave near Kingussie, which is likely to have been used for storage, defence or rituals during the Bronze and Iron Ages.
Staff at Orkney Research Centre for Archaeology (ORCA have now found a previously unknow strucure around 100 metres away.
A scattering of pottery sherds and a possible stone Ard point, likely to have been used as part of a plough, were also discovered.
The pottery was identified by Martin Carruthers, an Iron Age specialist at the University of the Highlands and Islands Archaeology Institute as a possible collection of early Iron Age sherds.
These finds led the archaeologists to believe that the structure may be associated with the souterrain.
Peter Higgins, Senior Project Manager ORCA, commented, “We are tremendously excited by these
finds in this archaeologically significant location.
“We are also pleased that we can work with Transport Scotland to make sure that these finds are recorded correctly without impeding the roadworks so vital to this Scotland’s economic development.”
Keith Brown Cabinet Secretary for Economy, Jobs and Fair Work said: “Our work to dual the A9 will bring undoubted improvements for road users including improved journey times and significantly improving road safety.
“At the same time, the ongoing design work has opened a window into Scotland’s past. We have already been able to shed more light on the Battle of Killiecrankie and now these latest finds on another stretch of the route offer evidence for experts on how our prehistoric descendants lived in the Iron Age.
Over 80 miles of road will be improved over the next 8 years as part of one of Scotland’s largest infrastructure projects.