 There is no evidence that Islay was ever subject to Roman military control although small numbers of finds such as a coin and a brooch from the third century AD suggest links of some kind with the intermittent Roman presence on the mainland.The ruins of a broch at Dùn Bhoraraic south east of Ballygrant and the remains of numerous Atlantic roundhouses indicate the influences of northern Scotland, where these forms of building originate.There are also various crannogs on Islay, including sites in Loch Ardnave, Loch Ballygrant and Loch Allallaidh in the south east where a stone causeway leading out to two adjacent islands is visible beneath the surface of the water.