County Donegal is situated in the north of the country in the province of Ulster and is part of the Republic of Ireland. Despite Lifford being the county town of Donegal, the largest town is Letterkenny. Letterkenny is a booming town with a university and huge out-of-town shopping hub. Ballybofey, the Heritage Town of Ramelton, Ardara located at the neck of three peninsulas near Glenties and Donegal town are among the long list of attractive and charming towns and villages in the county. The county is also the second-largest Gaeltacht area in the country and is a bastion of Gaelic culture and the Irish language. County Donegal is by far the most rugged and mountainous county in Ulster. The county consists chiefly of low mountains, with a deeply indented coastline forming natural loughs such as Lough Swilly and Lough Foyle. The county has two major ranges, the Derryveagh Mountains in the north and the Bluestack Mountains in the south, with Mount Errigal the highest peak. The Slieve League cliffs are the highest sea cliffs in Europe, while Donegal's Malin Head is the most northerly point in the country. Donegal is also home to Glenveagh National Park and Glenveagh Castle – a 140 km² nature reserve with spectacular scenery of mountains, raised bog lands, lakes and woodlands. Donegal's landscape lends itself to active sports like climbing, hill walking, golf, surfing and scuba diving. Surfing on Donegal's Atlantic coast is considered to be as good as any in Ireland; in particular the Victorian seaside resort of Bundoran is the main surfing hot spot in Ulster. There are many roads routes that the run through County Donegal. The main routes are the N15 which connects Sligo, Donegal town and Letterkenny, the N13 from Letterkenny to Derry and the N14 from Letterkenny which eventually links to the A4 to Omagh. County Donegal is served by both Donegal Airport, located at Carrickfinn in The Rosses in the west of the county, and by Derry Airport, located at Eglinton to the east. The closest railway station to the county is in Derry City.