A community archaeology event may have uncovered a previously unknown prehistoric settlement in the Highlands.
Led by a team of archaeologists, more than 40 people, including children, dug a series of trenches at Thusater Burn near Thurso.
A geophysical survey had suggested the remains of a building beneath the soil.
The dig revealed rubble, a hearth constructed from stone slabs, a hammer stone and other tools.
A "wonderfully preserved" pig's tooth was also found. Archaeologists said such a find was usually associated with high status sites.
Further investigations could confirm the remains to be a broch, or another type of prehistoric structure known as a wag.
The dig was organised by Caithness Broch Project and involved archaeologists from Orkney Research Centre for Archaeology (Orca) and the University of the Highlands and Islands.
Pete Higgins, Orca senior project manager, said: "It is incredibly exciting to be involved with the team from Caithness Broch Project and local people investigating this site, especially as this is the first time that it has been excavated.
"This is the first stage of a project which aims to investigate the wider prehistoric landscape of this area of northern Scotland and ultimately help provide the community with the tools to boost tourism in the area."
Caithness Broch Project member Kenneth McElroy added: "The dig was a really exciting community event - I was especially pleased to see that for many of the volunteers this was their first experience of an archaeological dig."