It is situated at the head of Loch Ryan, an arm of the North Channel (Irish Sea), 59 m.
On the coast of Loch Nell, or Ardmucknish Bay, is the vitrified fort of Beregonium, not to be confounded with Rerigonium (sometimes miscalled Berigonium) on Loch Ryan in Wigtownshire - a town of the Novantae Picts, identified with Innermessan.
It runs from the mouth of Loch Ryan in a sinuous north-easterly direction, keeping near the northern limit of the region till it reaches the basin of the Nith, where it quits the Uplands altogether, descends into the lowlands of Ayrshire, and, after circling round the headwaters of the Nith, strikes south-eastwards across half the breadth of the Uplands, then sweeps north and eastwards between the basins of the Clyde, Tweed and Annan, and then through the moors that surround.
In height, and on the west terminate in a long broken line of sea-wall, which begins at the mouth of Loch Ryan, extends to the Mull of Galloway, and reappears again in the southern headlands of Wigtown and Kirkcudbright.
- Ploucquet, Commentarius Medicus in processus criminales super homicidio et infanticidio, eec. (1736); Burke Ryan, Infanticide, its Law, Prevalence, Prevention and History (1862); G.