History, why it matters, and the nearest castle hotel to base yourself in — for every notable castle in Ireland. Every recorded site, famous or obscure, has its own page too — browse by county below.
A compact tower house on Achill Island guarding the strategic mouth of Achill Sound, strongly associated with Grace O'Malley, who is said to have used it to control shipping and levy tolls on vessels passing between the island and the mainland..
A four-storey tower house near Newport most famous as the base of Grace O'Malley ('Gráinne Mhaol'), the 16th-century pirate queen of Clan O'Malley, who moved in after marrying her second husband Richard 'an Iarainn' Bourke in 1566 and reputedly continued to run her seaborne operations from here.
A 13th-century Norman hall house in the village of Shrule on the Mayo–Galway border, one of the early Anglo-Norman fortified residences built as the de Burgo lordship expanded through Connacht along the River Black..
A 15th-century tower house extended into a fortified manor house by the Dowdall family in the 17th century, overlooking the River Boyne near Navan.
Begun around 1180-81 by Hugh de Lacy and held by the Plunkett family (Barons of Dunsany) since the early 15th century, it is one of Ireland's longest continuously occupied private homes.
Originally a Norman fortification held by the Cusack family from 1172 and later the Plunketts (Earls of Fingall) until 1951, it was remodelled in the 19th century into a grand Gothic Revival mansion by architect George Papworth.
Built for the Conyngham family from 1785 in Gothic Revival style overlooking the River Boyne, Slane Castle is internationally known as the venue for major rock concerts (U2, Rolling Stones, Bruce Springsteen).
Built by Hugh de Lacy on the banks of the River Boyne, Trim Castle is the largest Anglo-Norman castle in Ireland, with a distinctive 20-sided cruciform keep.
A vine-swathed 19th-century castle at the heart of the 1,000-acre Castle Leslie Estate near Glaslough, home to the Leslie family for generations, with three lakes, forests and horse trails across the grounds.
Originating as a motte-and-bailey built by the Gaelic O'Carroll clan, Birr Castle was granted to the Parsons family in 1620 and remains their home today.
Designed by Francis Johnston for Charles William Bury, 1st Earl of Charleville, and completed around 1812, it is regarded as one of the finest Gothic Revival castles in Ireland, set among ancient oak woodland in Tullamore.
Built on the site of a medieval O'Carroll stronghold and rebuilt from 1811-19 in Gothic Revival style for the Bernard family, Kinnitty Castle sits in the foothills of the Slieve Bloom Mountains.
An O'Carroll clan stronghold guarding the pass between the Slieve Bloom Mountains and the Munster border, Leap Castle is widely reputed to be the most haunted castle in Ireland, with a grim history including the 'Bloody Chapel' massacre.
A dramatic 13th-century Norman castle built in 1269 by Robert de Ufford, Justiciar of Ireland, with four D-shaped corner towers and a twin-towered gatehouse.
Known as 'the Castle of the Curlews', this Elizabethan-era blockhouse overlooking Lough Arrow was built during the Nine Years' War by Captain John St Barbe to guard the strategic Curlew Mountains pass.
A large rectangular keepless castle built around 1300 by Richard Óg de Burgh, 2nd Earl of Ulster ('the Red Earl'), to secure his newly won territory in south Sligo — regarded as the last of the great Norman castles built in Connacht.
Originally a fortified outpost of the Gaelic McDonagh clan guarding a ford across the River Unsin, it was granted to Cromwellian officer Cornet Edward Cooper in 1663.
Built in 1185 by Prince John on his first expedition to Ireland, Ardfinnan is one of the earliest Norman castles in the country, later managed by the Knights Templar and Knights Hospitaller.
One of Ireland's largest and best-preserved castles, built on a rocky island in the River Suir and granted to the powerful Butler family in the late 14th century.
A six-storey tower house with distinctive bartizans and tall chimneys, Kilcash was held by the Butlers of Ormond from the Irish Confederate Wars until the family sold it to the Irish State in 1997 for a nominal £500.
Built by Theobald Walter, 1st Baron Butler, and completed by his son around 1220, this cylindrical keep — over 30 metres high — was the principal Butler family stronghold before their move to Gowran.
Thomas Butler, 10th Earl of Ormond, added a Tudor manor house to the medieval castle in 1565 in honour of his cousin Queen Elizabeth I — the first unfortified great house of its kind in Ireland.