Excavations will continue until July
Neolithic remains which cast new light on the Isle of Man's earliest known inhabitants have been uncovered at the airport's new runway project.
The 5,000-year-old artefacts were found by workers within a 200ft (61m) stretch of the proposed taxiway extension.
As well as tools and pottery, experts found a human skull, a building, a rubbish dump and evidence of skull burials and funeral pyres.
Airport bosses say the find will not affect the runway extension schedule.
Excavations of the site are expected to continue until July, although experts from Oxford Archaeology are already convinced the site has "European significance".
"When the topsoil was stripped away, it revealed well-preserved archaeological remains, which date to the Neolithic period," said Fraser Brown, senior project manager of Oxford Archaeology North.
"These are specific to the Isle of Man and relate to what is known to archaeologists as the Ronaldsway Neolithic House, which was identified in 1943 following excavations for the original airfield.
"This latest find includes a rectangular 'sunken feature' building, which provides evidence of human habitation."
Mr Fraser said experts also found funerary and mortuary evidence, including stone cairns built over the top of pyres.
"It's a place where people lived and also where bodies were commemorated, with evidence of the burial of skulls and the burning of bodies.
"The excavation is of national significance for the Isle of Man, and is probably of European significance."
Archaeologists will continue to excavate the site, before recording and removing the artefacts.
Airport director Ann Reynolds said the "fascinating find" would have a minimal impact on the runway schedule.