Significant evidence of early Maori settlement in the Kamo area of Whangarei was discovered during work on a bypass last year.
Archaeologists found hangi pits, fire scoops, post holes and stone mounds, as well as charcoal believed to be almost 800 years old. Earthworks for the bypass were carried out under an archaeological Historic Places Trust authority.
Lead archaeologist Sarah Phear said radio-carbon dating techniques were used to place some of the features to around 1230-1275AD "with a high degree of certainty".
"We were surprised at how old the site was and also the fact that the site is so far away from the coast - which is quite rare for Northland."
Plant microfossil analysis indicated largescale clearance of forest using fire had taken place, Dr Phear said.