What is "twescard"

Twescard is a former county of the Earldom of Ulster in medieval Ireland. Taking its name from the native Irish territory of in Tuaiscirt, it spanned the northern coastland of County Antrim and County Londonderry. At its height it stretched from Glenarm in the east of the Glens of Antrim to Inishowen in modern County Donegal. It was conquered and settled by Hugh de Lacy and was centered on Coleraine and the lower Bush valley. By the 1460s, the de Mandevilles abandoned and sold their remaining lands in Twescard to the MacQuillans who renamed the territory the Route.