Bread ovens used by invading Roman soldiers are among ancient artefacts uncovered during excavations for the Aberdeen bypass.
Some of the items date back 15,000 years and include prehistoric roundhouses and a cremation complex.
Archaeologists have analysed the results of excavations at several locations around the Aberdeen Western Peripheral Route (AWPR) and say they indicate human activity in the area 2,000 years earlier than previously thought.
Bruce Mann, archaeologist for Aberdeenshire Council and Aberdeen City Council, said: "There has been a range of fascinating discoveries from the archaeological works carried out on site.
"Some raise more questions than they answer about what we thought we knew about the north east.
"For instance, a very unexpected discovery was the presence of Roman activity at Milltimber, likely dating from around 83/84 AD.
"Ninety bread ovens were uncovered, which were probably constructed by the Roman army at a time of invasion led by the Roman General Agricola."
He said the earliest finds included evidence of stone tool production dating from between 13,000 and 10,000 BC in the same area.
The cremated remains of a person in their 20s was found in a roundhouse and cremation complex at Nether Beanshill, dating to the Bronze Age, from around 1,600 to 1,250 BC.
Mr Mann said a highlight was a intact Beaker pot found at Milltimber dating from between 2,400 to 2,000 BC.
He added: "These archaeological finds provide real insight into the history and culture of the north east.
"They are impressive in both in time depth and range of activities represented.
"They push back known human activity in the region by at least 2,000 years, add new detail to how our ancestors lived and died, and reveal a new dimension to Rome's invasions of Scotland."
Keith Brown, Cabinet Secretary for Economy, Jobs and Fair Work, said: "The discoveries along the AWPR route, which would have remained undiscovered had the new bypass not been built, are truly remarkable and underline the importance of the value we place on meeting our environmental obligations as we plan and construct this new infrastructure."
A book on the artefacts uncovered will be published later this year and made available to schools and libraries.