THE REMAINS of what could be an Iron Age broch have been identified in a loch near Whiteness by a researcher from the University of Aberdeen.
Michael Stratigos found the site on one of the three Holms of Hogaland islets in the Loch of Strom.
He said the majority of the islet, which is the smallest of the three, is covered by a large mound around 3m high and 16x14m across.
It is unclear at the moment whether the find is the remains of a broch or of a roundhouse.
A small circular depression in the centre is believed to be the "internal space" of the structure.
There are also the potential remains of orthostats, or piers, while coursed stonework was noted.
Stratigos - who was assisted on the trip by Shetland-based underwater archaeologist Sally Evans - is currently studying archaeology and is focusing on crannogs, prehistoric dwellings built on offshore islets.
He said he was "incredibly pleased" to discover the remains after being told that there may have been a small causeway which led to the islet.
The researcher added that possible erosion is visible on one side of the islet.
"It is difficult to say how well preserved the site is without taking back some or all of the vegetation, something that would undoubtedly speed up the decay of the site," Stratigos said.
"What was clear though is that the south-west side of the island appears to be eroding, as there may be some stonework that relate to internal divisions of space that are now opening up to nothing, the loch having claimed most of whatever structure they related to.
"Return visits over a number of years carefully recording what changes would be the best way to quantify how quickly the erosion is taking place, if any.
"The archaeology team at Shetland Amenity Trust, the group Archaeology Shetland and a national research programme at St. Andrews, SCAPE, are keenly aware and focused on this kind of work on brochs and all other kinds of heritage at risk of coastal erosion."
Shetland Amenity Trust archaeologist Val Turner said the discovery was quite unusual due to its location in the loch.
"If it's not a broch and is an Iron Age house, then it's still significant because we don't have many large Iron Age houses, and we should have more."
There are currently at least 80 known broch sites in Shetland, but there could have been around 120 in total.
"The dimensions of this one are roughly comparable with the Mousa Broch, which is always said to be the smallest broch," Turner added.
"If we've got another one which has similar dimensions, then that's also quite exciting."
The find meanwhile comes just months after a member of the public found what appeared to be the remains of a Neolithic house on a beach in Lerwick.