Geography and political subdivisions
In terms of size and area, it is the largest county in Ulster and the fourth-largest county in all of Ireland. Uniquely, County Donegal shares a small border with only one other county in the Republic of Ireland – County Leitrim. The greater part of its land border is shared with three counties of Northern Ireland: County Londonderry, County Tyrone and County Fermanagh. This geographic isolation from the rest of the Republic has led to Donegal people maintaining a distinct cultural identity and has been used to market the county with the slogan "Up here it's different". While Lifford is the county town, Letterkenny is by far the largest town in the county with a population of 19,588. Letterkenny and the nearby city of Derry form the main economic axis of the northwest of Ireland. Indeed, what became the City of Derry was officially part of County Donegal up until 1610.
Poison Glen (Gleann Nimhe
), in North West Donegal
There are eight historic baronies in the county:
The county may be informally divided into a number of traditional districts. There are two Gaeltacht districts in the west: The Rosses (Irish: Na Rosa), centred on the town of Dungloe (Irish: An Clochán Liath), and Gweedore (Irish: Gaoth Dobhair). Another Gaeltacht district is located in the north-west: Cloughaneely (Irish: Cloich Chionnaola), centred on the town of Falcarragh (Irish: An Fál Carrach). The most northerly part of the island of Ireland is the location for three peninsulas: Inishowen, Fanad and Rosguill. The main population centre of Inishowen, Ireland's largest peninsula, is Buncrana. In the east of the county lies the Finn Valley (centred on Ballybofey). The Laggan district (not to be confused with the Lagan Valley in the south of County Antrim) is centred on the town of Raphoe.
As seen from the International Space Station
: Ulster coastline including Fanad peninsula, Lough Swilly, Inishowen, Lough Foyle and County Londonderry
According to the 1841 Census, County Donegal had a population of 296,000 people. As a result of famine and emigration, the population had reduced by 41,000 by 1851 and further reduced by 18,000 by 1861. By the time of the 1951 Census the population was only 44% of what it had been in 1841. As of 2016 , the county's population was 159,192.
||Population (2016 Census)
Horse riding on Tramore Beach in Downings
The county is the most mountainous in Ulster consisting chiefly of two ranges of low mountains; the Derryveagh Mountains in the north and the Blue Stack Mountains in the south, with Errigal at 749 metres (2,457 ft) the highest peak. It has a deeply indented coastline forming natural sea loughs, of which both Lough Swilly and Lough Foyle are the most notable. The Slieve League cliffs are the sixth-highest sea cliffs in Europe, while Malin Head is the most northerly point on the island of Ireland.
The climate is temperate and dominated by the Gulf Stream, with warm, damp summers and mild wet winters. Two permanently inhabited islands, Arranmore and Tory Island, lie off the coast, along with a large number of islands with only transient inhabitants. Ireland's second longest river, the Erne, enters Donegal Bay near the town of Ballyshannon. The River Erne, along with other Donegal waterways, has been dammed to produce hydroelectric power. The River Foyle separates part of County Donegal from parts of both counties Londonderry and Tyrone.
A survey of the macroscopic marine algae of County Donegal was published in 2003. The survey was compiled using the algal records held in the herbaria of the following institutions: the Ulster Museum, Belfast; Trinity College, Dublin; NUI Galway, and the Natural History Museum, London.
Records of flowering plants include Dactylorhiza purpurella (Stephenson and Stephenson) Soó.
The animals included in the county include the European badger (Meles meles L.).
There are habitats for the rare corn crake (Crex crex) in the county.