"Inishowen’s “ northern shore is the Atlantic Ocean; Lough Foyle forms its eastern boundary, and Lough Swilly its western. It is connected with the mainland on the south, and is, therefore, not an inis, or island, as its name implies, but a peninsula. …

Regarding its southern boundary we learn, by the Ordnance Survey that, ‘ about half the parish of Templemore, or what is generally called the northern liberties of Londonderry, was compromised in Inishowen, before the formation of the County of Londonderry, as is evident from an inquisition taken in Derry in the seventh year of the reign of James I., from which it appears that a jury composed of resident English and ancient Irish natives, of the principal septs of the district, ‘did upon their oaths find and present that the auncient and knowne meares of the country of Inishowen, alias O’Dogherties countrey, to the south and south-east, are and have been, tyme out of mynde, as followeth, viz., from the part or branch of Lough Swilly, on the weste and south-west parte of Birt, thorough the midst of a bog which extendeth to Lough Lappan from a well or spring upon Mullaghknockemona, and from the topp of that mountayne the meare extended through a small bog, which runneth alonge the top of the hill of Ardenemahill, and soe to the top of the hill Knockenagh, upon the easte part of which hill ariseth the streame of Altbally M’Rowertie, which runneth a meare betweene Bally Mac Rowertie in Inishowen, and parte of the landes of the Derry and Garrowgarle to the cawsy under Ellogh, and so down thorough the bog to Lough Swilly, and from the foresaid cawsy the meare of Inishowen aforesaid is thorough the midst of the Bog to Lough Foile."

(From “ Inishowen: Its History, Traditions, And Antiquities” by Maghtochair; 1867)

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