County Louth (Contae Lú) is in the East Coast and Midlands region of Ireland, and traditionally part of the province of Leinster. It's low-lying, fertile and within an hour's travel of Dublin, so it's densely populated, with Dundalk and Drogheda the main towns.
But I who have written this story, or rather this fable, give no credence to the various incidents related in it . . . - coda to the legend of Cú Chulainn
County Louth is a fertile lowland in Leinster, bordered to its east by the Irish Sea and to its north by the brooding mountains of Ulster. So it's always been on the frontier of the badlands, and Irish legends thunder with the stories of its supernatural and superhuman conflicts. Louth itself is named after Lugh, a multi-talented warrior god who devised a Gaelic precursor to chess. One major legend-cycle, Táin Bó Cúailnge or "The Cooley Cattle Raid", may have been written down as early as the 8th century AD. Its ostensible MacGuffin is ownership of a prize bull, but it's really about the struggle between Ulster and other regional rulers, notably Queen Medh or Maeve of Connacht. An ancestral curse renders the Ulstermen too weak to fight, except for the teenage hero Cú Chulainn, son of Lugh, who in episode after episode defeats the invaders-cum-rustlers.
The terrain made this an easy place to reach by sea, and worth grabbing - the first well-documented invaders being the Vikings. But it was the 12th century Normans who really stamped their mark on it, with their castles, city walls and monastic foundations, and establishment of a county structure close to the modern pattern. The Tudors consolidated the castles, walls and counties while destroying the monasteries with the Dissolution and Reformation. Several battles were fought around Louth that were extensions of wars in Great Britain. In the 14th century Robert Bruce trounced the English at Bannockburn and became king of Scotland: his brother Edward thought to get in on the fun and got himself crowned High King of Ireland, but 3 years later was defeated and killed near Dundalk. In the 17th century Oliver Cromwell, having beheaded the king of England, opened his campaign in Ireland with a notorious massacre at Drogheda. And late in that century King James II / VII, deposed in England, made Ireland his platform for regaining his throne. His forces faced off against those of King William III across the River Boyne a few km upstream from Drogheda. A defeated James fled into exile, while William advanced to Dublin and ensured Protestant minority rule throughout Ireland.
Thereafter came two mostly peaceful centuries in which Drogheda and Dundalk became large industrial towns, blunting the impact of the famine years, and creating their present layout. The county's long sandy beaches became resorts, and golf clubs were the new cash crop in the fields. Partition of Ireland and the late 20th century "Troubles" cast a pall over Dundalk, but the bigger problem was the twilight of traditional industries and lack of new growth. County Louth has revived somewhat in the 21st century as the commuter belt for thriving Dublin.
Dublin (IATA: DUB) is the best option for its wide range of budget flights, and proximity, with buses direct to Drogheda and motorway links north.
The two Belfast airports are little over an hour's drive to Dundalk.
Dundalk no longer has passenger ferries. Belfast, Dublin and Rosslare have ferries from Great Britain and the Isle of Man, and good onward transport.
In summer a car ferry crosses the outlet of Carlingford Lough, connecting Greenore with Greencastle in County Down. So it's a shortcut to the scenic Mourne Mountains.
Commuter trains run every 30 min from Dublin Connolly to Drogheda. Every couple of hours, the Enterprise Train links Dublin, Drogheda, Dundalk, Newry, Portadown and Belfast Lanyon Place.
Dublin Connolly also has commuter trains from around the city, inter-city trains to Wicklow, Arklow, Wexford and Rosslare (for ferries to Wales), and inter-city trains to Mullingar, Longford, Boyle and Sligo. In Dublin allow 45 min to change stations for trains from Cork, Limerick and Galway, which run to Dublin Heuston.
Buses from Dublin run via the airport (which doesn't have a railway link) to Drogheda. Inter-city buses from the north don't stop in the county, so from Belfast take the train. There are cross-border buses between Newry and Dundalk but they're slow and roundabout.
M1 from Dublin to Belfast traverses the county. Get off at Exits 7, 8, 9 and 10 for Drogheda, and Exits 16, 17 and 18 for Dundalk. There's a toll between Exits 7 and 8.
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