Castle Rock at Auchmithie bears the remains of a—probably Iron Age—promontory fort. The situation is breath-taking, guarded by 30 metre cliffs rising vertically from the shingle beach below. Sadly, the actual site of the fort is impossible to visit these days as it is in the embrace of the thickest expanse of mature gorse imaginable. To reach the site you would have to come armed with loppers and a sturdy saw!
The Fort is reported to be protected by means of three curved banks with:
"medial ditches, broken by a central entrance causeway 2 metres wide. The fort was diminutive, the level enceinte being c.30.4 metres square, but now considerably eroded on the north, and to a lesser extent on the east. The site was surveyed in 1958 by the OS, and was excavated between 1967-1974. Features included various postholes, and hearths were associated with a floor, possibly a single circular structure with a porch or a series of windbreaks, or lean-to shelters".
More information, including an aerial photograph, is available at RCAHMS.