County Dublin in the context of "Leinster"

The Irish Sea is a 46,007 km (17,763 sq mi) body of water that separates the islands of Ireland and Great Britain. It is linked to the Celtic Sea in the south by St George's Channel and to the Inner Seas off the West Coast of Scotland in the north by the North Channel. Anglesey, North Wales, is the largest island in the Irish Sea, followed by the Isle of Man. The term Manx Sea may occasionally be encountered (Welsh: Môr Manaw, Irish: Muir Meann Manx: Mooir Vannin, Scottish Gaelic: Muir Mhanainn).

On its shoreline are Scotland to the north, England to the east, Wales to the southeast, Northern Ireland and the Republic of Ireland to the west. The Irish Sea is of significant economic importance to regional trade, shipping and transport, as well as fishing and power generation in the form of wind power and nuclear power plants. Annual traffic between Great Britain and Ireland is over 12 million passengers and 17 million tonnes (17,000,000 long tons; 19,000,000 short tons) of traded goods.

Dublin is the capital and largest city of Ireland. Situated on Dublin Bay at the mouth of the River Liffey, it is in the province of Leinster, and is bordered on the south by the Dublin Mountains, part of the Wicklow Mountains range. Dublin is the largest city by population on the island of Ireland; at the 2022 census, the city council area had a population of 592,713, while the city including suburbs had a population of 1,263,219, County Dublin had a population of 1,501,500. Various definitions of a metropolitan Greater Dublin Area exist.

A settlement was established in the area by the Gaels during or before the 7th century, followed by the Vikings. As the Kingdom of Dublin grew, it became Ireland's principal settlement by the 12th century Anglo-Norman invasion of Ireland. Dublin expanded rapidly from the 17th century and was briefly the second largest in the British Empire and sixth largest in Western Europe after the Acts of Union in 1800. Following independence in 1922, Dublin became the capital of the Irish Free State, renamed Ireland in 1937. As of 2018, Dublin was listed by the Globalization and World Cities Research Network (GaWC) as a global city, with a ranking of "Alpha minus", which placed it among the top thirty cities in the world.

Dún Laoghaire (/dʌn ˈlɪəri/ dun LEER-ee, Irish: [ˌd̪ˠuːn̪ˠ ˈl̪ˠeːɾʲə, - ˈl̪ˠiːɾʲə]) is a suburban coastal town in County Dublin in Ireland. It is the administrative centre of the county of Dún Laoghaire–Rathdown. The town was built up alongside a small existing settlement following 1816 legislation that allowed the building of a major port to serve Dublin. It was known as Dunleary in the English language, until it was renamed Kingstown in honour of King George IV's 1821 visit, and in 1920 was given its present name, which is the original Irish form from which "Dunleary" was anglicised. Over time, the town became a residential location, a seaside resort, the terminus of Ireland's first railway and the administrative centre of the former borough of Dún Laoghaire, and from 1994, of the county of Dún Laoghaire–Rathdown.

The Kingdom of Dublin (Old Norse: Dyflin) was a Norse kingdom in Ireland that lasted from roughly 853 AD to 1170 AD. It was the first and longest-lasting Norse kingdom in Ireland, founded by Vikings who invaded the territory around Dublin in the 9th century. Its territory corresponded to most of present-day County Dublin.

County Meath (/miːð/ MEEDH; Irish: Contae na Mí or simply an Mhí, lit. 'middle') is a county in the Eastern and Midland Region of Ireland, within the province of Leinster. It is bordered by County Dublin to the southeast, Louth to the northeast, Kildare to the south, Offaly to the southwest, Westmeath to the west, Cavan to the northwest, and Monaghan to the north. To the east, Meath also borders the Irish Sea along a narrow strip between the rivers Boyne and Delvin, giving it the second shortest coastline of any county. Meath County Council is the local authority for the county.

Meath is the 14th-largest of Ireland's 32 traditional counties by land area, and the 8th-most populous, with a total population of 220,826 according to the 2022 census. The county town and largest settlement in Meath is Navan, located in the centre of the county along the River Boyne. Other towns in the county include Trim, Kells, Laytown, Ashbourne, Dunboyne, Slane and Bettystown.

The Wicklow Mountains (Irish: Sléibhte Chill Mhantáin, archaic: Cualu) form the largest continuous upland area in Ireland. They occupy the whole centre of County Wicklow and stretch outside its borders into the counties of Dublin, Wexford and Carlow. Where the mountains extend into County Dublin, they are known locally as the Dublin Mountains (Sléibhte Bhaile Átha Cliath). The highest peak is Lugnaquilla at 925 metres (3,035 feet).

The mountains are primarily composed of granite surrounded by an envelope of mica-schist and much older rocks such as quartzite. They were pushed up during the Caledonian orogeny at the start of the Devonian period and form part of the Leinster Chain, the largest continuous area of granite in Ireland and Britain. The mountains owe much of their present topography to the effects of the last ice age, which deepened the glens and created corrie and ribbon lakes. Copper and lead have been the main metals mined in the mountains and a brief gold rush occurred in the 18th century.Several major river systems have their source in the mountains, such as the Liffey, Dargle, Slaney and Avoca rivers. Powerscourt Waterfall is the second tallest in Ireland at 121 metres (397 feet). A number of these rivers have been harnessed to create reservoirs for drinking water for Dublin and its surroundings.

The Greater Dublin Area (GDA; Irish: Mórcheantar Bhaile Átha Cliath), or Greater Dublin, is an informal term that is taken to include the city of Dublin and its hinterland, with varying definitions as to its extent. At the expansive end, it has been defined as including all of County Dublin and three neighbouring counties, while more commonly it is taken as the contiguous metropolitan area of Dublin plus suburban and commuter towns. The area is defined for strategic planning, and, for example, transport, and it is not a formal administrative or political unit.

Summerhill House was a 100-roomed Palladian house in County Meath, Ireland which was the ancestral seat of the Viscounts Langford and the Barons Langford. Built in 1731, it was likely designed by Sir Edward Lovett Pearce and completed by Richard Cassels in the Palladian style, although Sir John Vanbrugh, who was related to Pearce and with whom he trained, is thought to have also influenced the design of the house, which could be seen by the Baroque details, great arched chimney stacks and the palatial grandeur and scale.

The house demonstrated the power and wealth the Langford Rowley family had at the time. They owned vast amounts of land in counties Meath, Westmeath, Cork, Londonderry, Antrim, and Dublin as well as in Devon and Cornwall in England. The house also welcomed royalty, and ranked architecturally amongst the finest and most modern mansions in Europe.

The Hospital and Free School of King Charles II, Oxmantown, also called The King's Hospital (KH; Irish: Scoil Ospidéal an Rí) is a Church of Ireland co-educational independent day and boarding school situated in Palmerstown, County Dublin, Ireland. It is on an 80-acre campus beside the River Liffey, called Brooklawn, named after the country houses situated on the site and in which the headmaster and his family reside. The school is also a member of the HMC Headmasters' and Headmistresses' Conference and the BSA.

Founded in 1669, it is one of the oldest schools in Ireland and was also known as the Blue Coat School. Although priority is given to those of the main Protestant denominations, as a Christian school, it is attended by students of other Christian denominations and other faiths. The school's colours are navy and gold. The school crest is three burning castles with the date "1669", almost identical to the crest for Dublin city. The current headmaster is Mark Wallace.