Prehistoric remains have been uncovered during work on a £120 million water mains network upgrade between Ayrshire and Glasgow.

Archaeologists have discovered the remains of an early Neolithic structure believed to have been built by the earliest farmers in Scotland around 6,000 years ago.

The find was made in countryside near Kilmarnock while Scottish Water was working on the multi-million water project.

The company and its alliance partners, Caledonia Water Alliance (CWA) and GUARD Archaeology, will now liaise with the West of Scotland Archaeology Service (WoSAS following the discovery.

Kenneth Green, excavation director at GUARD Archaeology of Glasgow, said: “This is one of the most important discoveries of this type in south west Scotland in recent years.

“Heavily truncated by millennia of ploughing, only the deepest parts of some of the post-holes survived, arranged in a rectangular plan and containing sherds of early Neolithic pottery, hazelnut shell and charcoal.

“The width and depth of these post-holes indicated that they once held very large upright timber posts, suggesting that this building was once a large house, probably home to an extended family or group of families.

“Up until this time, during the earlier Mesolithic period (c. 8000-4000 BC), Scotland was inhabited by small groups of hunter gatherers, who led a nomadic lifestyle, living off the land.

“The individuals who built this Neolithic house were some of the earliest communities in Ayrshire to adopt a sedentary lifestyle, clearing areas of forest to establish farms, growing crops such as wheat and barley and raising livestock such as cattle, sheep, goats and pigs.”

Andrew Grant, an environmental advisor for Scottish Water, said: “As part of the project planning, Scottish Water identified the possibility of archaeology and so factored in time for the area to be excavated.

“However, the discoveries are even more significant than we had expected and we are delighted that, with the archaeologists’ help and expertise, we have been able to uncover something of such importance.”