Remains dating back to the Bronze Age have been uncovered by archaeologists excavating the site of a 9th Century monument.
The finds were made during the latest dig at the Pillar of Eliseg near Llangollen, Denbighshire.
Possible cremated remains and bone fragments are now being examined.
The experts said the finds had complicated the picture regarding the site's historical significance and make it worthy of more investigation.
Bangor and Chester university experts and students have been involved in a dig with historical monuments agency Cadw to conserve and better understand the mound.
They gave updates, and shared photographs and films via Llangollen Museum's Facebook page during the dig.
Last year's excavations focused on the mound, which was identified as an early Bronze Age cairn.
It is said the local landowner Trevor Lloyd re-erected the monument on the mound in 1773 after it fell over and found a grave with a body inside along with pieces of silver.
The experts have been trying to find if there any truth to the story which some think is legend.
Prof Nancy Edwards from Bangor University said to establish any truth in the story they had to clear away debris left by Lloyd more than 200 years ago.
"We have been digging that out to reveal what we think are the Bronze Age remains underneath," she said.
"We have had what we think is an early medieval long cist grave so it is looking even more complicated now and also what may be evidence of Bronze Age cremations."
The Pillar of Eliseg was originally a tall stone cross but only part of a round shaft survives set within its original base.
It once bore a long Latin inscription saying that the cross was raised by Concenn, ruler of the kingdom of Powys, who died in AD 854, in memory of his great-grandfather, Eliseg, who had driven Anglo-Saxon invaders out of the area.
An update on the latest finds will be published in the near future.