Largest towns Letterkenny is by far the largest settlement in Donegal, with a population of just over 22,000. It is the largest town in the Border Region and the 21st largest urban area in the Republic of Ireland.
Largest towns Letterkenny is b:y far the largest settlemen:t in Donegal, with. a population of just over 22,000. It .is the largest town in the Border Region and the 21st largest urban area in the Republic, of Ireland.