This articles lists the islands of County Mayo, the mainland of which is part of the island of

Ireland Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...

. Included in this list are named offshore and freshwater islands as recorded by

Ordnance Survey Ireland Ordnance Survey Ireland (OSI; ga, Suirbhéireacht Ordanáis Éireann) is the national mapping agency of Ireland. It was established on 4 March 2002 as a body corporate. It is the successor to the former Ordnance Survey of Ireland. It and the ...

or the

Placenames Database of Ireland The Placenames Database of Ireland ( ga, Bunachar Logainmneacha na hÉireann), also known as , is a database and archive of place names in Ireland. It was created by Fiontar, Dublin City University in collaboration with the Placenames Branch of t ...

. Additionally, areas of ecological significance related to both offshore and freshwater islands, designated by the National Parks and Wildlife Service, are also listed. Although

County Mayo County Mayo (; ga, Contae Mhaigh Eo, meaning "Plain of the Taxus baccata, yew trees") is a Counties of Ireland, county in Republic of Ireland, Ireland. In the West Region, Ireland, West of Ireland, in the Provinces of Ireland, province of Conn ...

has hundreds of offshore and freshwater islands, only a handful of islands and island groups are large enough to be distinguishable on a typical map of the county, namely

Achill Island Achill Island (; ga, Acaill, Oileán Acla) in County Mayo is the largest of the Irish isles, and is situated off the west coast of Republic of Ireland, Ireland. It has a population of 2,594. Its area is . Achill is attached to the mainland by ...

Clare Island Clare Island ( or ''Oileán Chliara''), also historically Inishcleer, is a mountainous island guarding the entrance to Clew Bay in County Mayo, Ireland. Historically part of the kingdom of Umhaill, it is famous as the home of the 15th century pi ...

and

Inishturk Inishturk (''Inis Toirc'' in Irish, meaning ''Wild Boar Island'') is an inhabited island of County Mayo, in Ireland. Geography The island lies about off the coast; its highest point reaches above sea level. Between Inisturk and Clare Islan ...

, along with the island clusters of

Duvillaun Duvillaun (English: Black Island; Irish: Dubhoileán) is the name of a cluster of islands lying south to the Inishkea Islands and Inishglora in the Atlantic Ocean off the coast of North Mayo. The main island is known as Duvillaun More (Big Bla ...

, Inishkea,

Clew Bay Clew Bay (; ga, Cuan Mó) is a natural ocean bay in County Mayo, Republic of Ireland. It contains Ireland's best example of sunken drumlins. The bay is overlooked by Croagh Patrick to the south and the Nephin Range mountains of North Mayo. C ...

and the major loughs. There are over 100 islands which are greater than in area. The largest island is Achill, which extends to , making it Ireland's largest offshore island. Due to its abundance of bays, inlets and offshore islands, Mayo is reputed to have the longest coastline of any county in Ireland, at or approximately 21% of the total coastline of the State. The geology and geomorphology of the county and its islands is among the most varied and complex in Ireland. Islands such as those at Clew Bay are low-lying, formed when

rising sea levels Rising may refer to: * Rising, a stage in baking - see Proofing (baking technique) *Elevation * Short for Uprising, a rebellion Film and TV * "Rising" (''Stargate Atlantis''), the series premiere of the science fiction television program ''Starga ...

drowned a vast field of

drumlins A drumlin, from the Irish word ''droimnín'' ("littlest ridge"), first recorded in 1833, in the classical sense is an elongated hill in the shape of an inverted spoon or half-buried egg formed by glacial ice acting on underlying unconsolidated ...

, while others like Clare Island and Achill are characterised by mountains and towering sea-cliffs, of which

Croaghaun Croaghaun ( ga, Cruachán) is a mountain on Achill island in County Mayo, Ireland. At 688 metres (2,257 ft), it has the highest sea cliffs in Ireland as well as the third highest sea cliffs in Europe (after Hornelen, Norway and Cape Enni ...

are the third-highest in

Europe Europe is a large peninsula conventionally considered a continent in its own right because of its great physical size and the weight of its history and traditions. Europe is also considered a Continent#Subcontinents, subcontinent of Eurasia ...

, at The bedrock geology of the islands is broadly divided into two groups. Those north of Clew Bay such as Achill and the islands off the

Mullet Peninsula The Mullet Peninsula ( ga, Leithinis an Mhuirthead)—also known as the Mullet (''an Mhuirthead'') and sometimes as the Erris Peninsula—is a peninsula in the barony of Erris in County Mayo, Ireland. As of 2016 it has a population of 3963. I ...

are generally of ancient

Dalradian The Dalradian Supergroup (informally and traditionally the Dalradian) is a stratigraphic unit (a sequence of rock strata) in the lithostratigraphy of the Grampian Highlands of Scotland and in the north and west of Ireland. The diverse assemblag ...

age, similar to

Donegal Donegal may refer to: County Donegal, Ireland * County Donegal, a county in the Republic of Ireland, part of the province of Ulster * Donegal (town), a town in County Donegal in Ulster, Ireland * Donegal Bay, an inlet in the northwest of Ireland b ...

and the Grampian Highlands. Inishglora contains some of the oldest rocks in Ireland, at 1.75 billion years old. Further south, the islands are much more diverse. Clare island alone is composed of

Cambrian The Cambrian Period ( ; sometimes symbolized C with bar, Ꞓ) was the first geological period of the Paleozoic Era, and of the Phanerozoic Eon. The Cambrian lasted 53.4 million years from the end of the preceding Ediacaran Period 538.8 million ...

Ordovician The Ordovician ( ) is a geologic period and System (geology), system, the second of six periods of the Paleozoic Era (geology), Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start ...

Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at million years ago ( Mya), to the beginning of the Devonian Period, Mya. The Silurian is the shortest period of the Paleozo ...

and

Carboniferous The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carbonifero ...

terrane In geology, a terrane (; in full, a tectonostratigraphic terrane) is a crust fragment formed on a tectonic plate (or broken off from it) and accreted or " sutured" to crust lying on another plate. The crustal block or fragment preserves its own ...

s sutured together. Geologically, the Clew Bay islands themselves are the youngest in the county, formed during the

Lower Carboniferous Lower may refer to: *Lower (surname) *Lower Township, New Jersey *Lower Receiver (firearms) *Lower Wick Lower Wick is a small hamlet located in the county of Gloucestershire, England. It is situated about five miles south west of Dursley, eight ...

about 350 million years ago. The county's offshore islands - and islands off the west coast of Ireland generally - developed their own distinct culture and traditions stretching back centuries. Records from the 1841 Census show that 47 of County Mayo's offshore islands were inhabited, with a combined population of approximately 10,000. The Great Famine resulted in widespread or total

depopulation A population decline (also sometimes called underpopulation, depopulation, or population collapse) in humans is a reduction in a human population size. Over the long term, stretching from prehistory to the present, Earth's total human population ...

of the islands. Towards the end of the 19th century the population of the larger islands began to recover somewhat, only to be set back by emigration following

independence Independence is a condition of a person, nation, country, or state in which residents and population, or some portion thereof, exercise self-government, and usually sovereignty, over its territory. The opposite of independence is the statu ...

as the

Irish government The Government of Ireland ( ga, Rialtas na hÉireann) is the cabinet that exercises executive authority in Ireland. The Constitution of Ireland vests executive authority in a government which is headed by the , the head of government. The governm ...

initially encouraged the evacuation of the islands due to the cost of providing services to them, further hastening the decline. Today, the islands are recognised by the

State State may refer to: Arts, entertainment, and media Literature * ''State Magazine'', a monthly magazine published by the U.S. Department of State * ''The State'' (newspaper), a daily newspaper in Columbia, South Carolina, United States * ''Our S ...

as an integral part of Ireland's national heritage, preserving the remnants of a unique aspect of

Irish culture The culture of Ireland includes language, literature, music, art, folklore, cuisine, and sport associated with Ireland and the Irish people. For most of its recorded history, Irish culture has been primarily Gaelic (see Gaelic Ireland). It has ...

. The remaining inhabited islands receive support and funding through the

Department of Culture, Heritage and the Gaeltacht The Department of Tourism, Culture, Arts, Gaeltacht, Sport and Media ( ga, An Roinn Turasóireachta, Cultúir, Ealaíon, Gaeltachta, Spóirt agus Meán) is a department of the Government of Ireland. The mission of the department is to promote a ...

. As of the 2016 Census, there are 2,700 people living on 14 of the county's offshore islands (of which 2,440 live on Achill), accounting for 1.87% of the county's population. Keem Bay, Achill Island Co

Islands of Mayo by population

Demographics

The 2016 census records 14 offshore islands as having a usually resident population. Achill has been connected to the mainland via bridge since 1887, making Clare Island the county's most populous unconnected island, with 159 inhabitants as of 2016. This makes Clare Island the fifth-most populous unconnected island in Ireland, after the three

Aran Islands The Aran Islands ( ; gle, Oileáin Árann, ) or The Arans (''na hÁrainneacha'' ) are a group of three islands at the mouth of Galway Bay, off the west coast of Republic of Ireland, Ireland, with a total area around . They constitute the histo ...

off Galway and

Arranmore ''Árainn Mhór'' (English name: Arranmore) is an island off the west coast of County Donegal, Ireland. Arranmore is the largest inhabited island of County Donegal, with a population of 469 in 2016, but has had a gradually falling native popula ...

off Donegal.

Mayo County Council Mayo County Council ( ga, Comhairle Contae Mhaigh Eo) is the authority responsible for local government in County Mayo, Ireland. As a county council, it is governed by the Local Government Act 2001. The council is responsible for housing and co ...

is responsible for the governance of the islands, and islanders are entitled to certain benefits and exemptions, such as lower motor tax rates. The islands also receive funding from the Department of Culture, Heritage and the Gaeltacht, as several offshore islands along with much of northwest Mayo are recognised

Gaeltacht ( , , ) are the districts of Ireland, individually or collectively, where the Irish government recognises that the Irish language is the predominant vernacular, or language of the home. The ''Gaeltacht'' districts were first officially recog ...

areas.

Fish Curing on Clare Island (7108837815)

As many as 47 offshore islands had permanent populations prior to the Great Famine. Communities had resided on these islands for generations, and their remains can still be seen to this day through the villages, stone walls and lazybeds which they left behind. By the end of the 19th century most of the county's islands had been deserted. In contrast, Achill benefitted from a bridge to the mainland which allowed the population to temporarily rebound, reaching its all-time peak in 1911. Emigration from the islands continued into the 20th-century as traditional industries such as fishing and textiles were unable to provide an attractive, or in many cases adequate, income to young islanders. In recent times, the islands have become a popular tourist destination and depend heavily on the tourism and hospitality sector. Their population swells during the summer months, particularly on Achill and Clare. Popular activities include surfing, sailing, island-hopping in Clew Bay, spiritual retreats and

eco-tourism Ecotourism is a form of tourism involving responsible travel (using sustainable transport) to natural areas, conserving the environment, and improving the well-being of the local people. Its purpose may be to educate the traveler, to provide funds ...

. The following table shows population trends for the fourteen currently inhabited islands as of the last census. The overall trend is a continuing decline in the population of Mayo's offshore islands, which is currently at a historic low. The county as a whole was one of just three in Ireland to record a population decrease between 2011 and 2016. The population of Mayo during this time decreased by 0.2%, whereas the population of the islands fell by 5.3%. Although the overall population fell during this time, four previously uninhabited islands received new residents, including Achillbeg, which had been uninhabited since 1965.

Currently inhabited islands

Formerly inhabited islands

Islands of Mayo by area

Larger islands

With the exception of Achill, County Mayo's islands are generally small in size, with only 13 larger than and 3 larger than . There are numerous offshore islands in the 10 to 100 acre range, along with at least 15 freshwater islands larger than 10 acres, the largest of which is Illannaglashy on

Lough Conn Lough Conn () is a lake in County Mayo, Ireland. With an area of about , it is Ireland's seventh largest lake. With its immediate neighbour to the south, Lough Cullin, it is connected to the Atlantic Ocean by the River Moy. Lough Conn is noted ...

at . The one hundred largest islands in the county are listed below. "F" designates a freshwater island. IRL Jan99 26 (9277948677)

Bartragh Island from Bartragh Head - geograph

Rosturk Clew Bay geograph-3180700-by-Ben-Brooksbank

Kid Island, Kilcommon, Erris, North Mayo

Smaller offshore islands

County Mayo has hundreds of smaller islands and islets. Most of the county's offshore islands are located in Clew Bay, with smaller clusters located around the Achill archipelago, the west and south coasts of the

, and

Blacksod Bay Blacksod Bay ( ga, Cuan an Fhóid Duibh) is a bay of the Atlantic Ocean in Erris, north County Mayo, Ireland. The long and wide bay is bounded on its western side by the Mullet Peninsula. Its eastern side includes Kiltane Parish, which ext ...

. The list below is not exhaustive, and includes named offshore islands that are either extensive (typically greater than 2 acres in area) or in someway locally significant or identifiable. Unlike the above list, this list is in alphabetical order and does not include freshwater islands. Clew bay-old map

Black Rock Island - County Mayo - Ireland

Freshwater islands

There are numerous large loughs within the county, containing hundreds of small freshwater islands.

Lough Mask Lough Mask () is a limestone lake of about in Counties Mayo and Galway, Ireland, north of Lough Corrib. Lough Mask is the middle of the three lakes, which empty into the Corrib River, through Galway, into Galway Bay. Lough Carra flows into ...

in southern Mayo is the largest lough in the county. At it is the 6th-largest lough in Ireland (as well as the 6th-largest in Britain and Ireland). Further south,

Lough Corrib Lough Corrib ( ; ) is a lake in the west of Ireland. The River Corrib or Galway River connects the lake to the sea at Galway. It is the largest lake within the Republic of Ireland and the second largest on the island of Ireland (after Lough Nea ...

is the 2nd-largest lough in Ireland; however, only a small portion of this lough is located within the county. Illannaglashy, on

, is the largest freshwater island in the county, at in area. Freshwater islands have played an important role in the county's history and host an abundance of castles, monasteries, church ruins and unspoiled woodlands.

Lough Mask

Castleburke Castle on Lough Carra Co Mayo

*''Note: The vast majority of

is within County Mayo, with a small southern portion of the lough located in County Galway. This list only includes islands which are within the boundary of County Mayo.'' *Aghinish *Bed Island *Bilberry Island *Black Island *Black Island *Board Island *Carrigeen Island *Carrigeen Middle *Carrigeenabreana *Carrigeenagur Island *Carrigeenamore *Carrigeenavilla *Carrigeenaweelaun *Carrigeenbaun *Carrigeenbunnahown *Carrigeendany Islands *Carrigeenduree *Carrigeenfair Island *Carrigeenkeelagh *Carrigeenmauntrasna *Carrigeennagool *Carrigeennalogh *Carrigeennasassonagh *Carrigeenowen *Carrigeenshangorman *Castle Hag *Cow Island *Dash Island *Devenish Island *Doran Islands *Goat Island *Green Island *Gull Island *Flag Island *Heath Island *Illan Columbkille *Illanboe Beg *Illanboe More *Illandawaur *Ingon Island *Inishangan *Inishdurra *Inishgleasty *Inishoght *Inishowenlackboy *Inishrobe *Kid Island *Lackboy *Lamb Island *Long Island *Long Islands *Lusteen Beg *Lusteen More *Nut Island *Oak Island *Pig Island *Rams Island *Rialisk *Ringolden *River Island *Saints Island *Seerillaun *Shangorman *Shrub Island *Thick Island *Whiteland Island

Lough Carra

*Ballycally Island *Bird Island *Bonnianillish Island *Bush Island *Carrigeennagat Island *Castle Island *Castlehag Island *Church Island *Conors Island *Cow Islands *Crane Island *Creevagh Island *Deer Island *Derrinrush Island *Derrynafresha Island *Doonbeg Island North *Doonbeg Island South *Gleneary Island *Hog Island *Horse Island *Illanatrim *Kiln Island *Lady's Island *Lakeview Island *Leamnahye Island *Long Island *Mearing Island *Otter Island *Otter Island *Otter Islands *Pleasure Island *Priest Island *Rat Island *Stare Island *Stony Island

Lough Corrib

*''Note: The vast majority of

is within County Galway, with a small northern portion of the lough located in County Mayo. This list only includes islands which are within the boundary of County Mayo.'' *Abbots Rock *Ballycurrin Island *Bartragh Island *Bertragh Islands *Blackderry Island *Blackderry Rock *Bushy Island *Camillaun *Carrigeen *Castletown Rock *Cornelian Islands *Crow Islands *Dog Islands *Easter Island *Flower Island *Gibbs Islands *Grass Island *Green Island *Green Island East *Holy Island *Inishkeeragh Island *Island Morris *Kilmore *Kilmorebeg *Matthew Island *Mine Island *Mucky Island *Oak Island *Prison Islands *Rabbit Island *Red Island *Salmon Island *Salmon Point Island *Sloe Island *Whiskey Island

Lough Conn

*Annagh Island *Annaghroe Island *Annaghteige Island *Bears Island *Burnt Island *Carnaweelan Island *Castle Island *Chain Island *Cliff Island *Coarse Island *Cragh Islands *Creeve Island *Freaghillan *Illanaghty *Illanaloughaun *Illanbeg *Illannaglashy *Inishlee Island *Longford Island *Loosky Island *Rinard Island *Rocky Island *Roe Island *Sandy Island

Smaller lakes

Lough Cullin

*Griffins Island *Illanboy *Illaner *Illangub *Illanneill *Illanulque

Lough Beltra

*Bush Island *Coarse Island *Islandmore *Low Island *Tree Island

Carrowmore Lake

*Atlavally Island *Derreens Island *Gortmore Island *Muingerroon Island

Furnace Lough

*Illanroe *Inishower *Saints Island

Islandeady Lough

*''Note: Despite being a small lough, Islandeady had three sizeable islands, at 38, 21 and 20 acres respectively. However, due to the lowering of waterlevels in the 20th century the three islands are now peninsulas. '' *Illanlteige East *Illanteige West *Islandeady

Monastic islands

Six islands within County Mayo have had a dedicated monastery or abbey established on them. Four of these are offshore, and two of these are freshwater islands. They are listed below: * Church Island Monastery (F) * Clare Island Abbey * Duvillaun Monastery * Inishkea North Monastery * Inishglora Monastery * Partry Monastery (F) In addition to the above sites, many more islands within the county have been used for religious purposes. The ruins of old churches and cemeteries can be found scattered across such islands.

Biodiversity

Many of the county's offshore and freshwater islands are designated as areas of ecological significance and are protected both at national and European level. Mayo's offshore islands are a haven for wildlife and biodiversity, supporting hundreds of species of bird, fish and marine mammal, as well as unique vegetation. Five of the county's major inland lakes (along with their islands) are also protected, those being Lough Mask, Lough Conn, Lough Cullin, Lough Carra and Carrowmore Lake.National Parks and Wildlife Service - Protected Sites
/ref> The biodiversity of the islands is protected under the following designations. There is overlap across designations, as different designations apply to different species, e.g. the Duvillaun Islands are an SAC, SPA and proposed NHA. *

Special Area of Conservation A Special Area of Conservation (SAC) is defined in the European Union's Habitats Directive (92/43/EEC), also known as the ''Directive on the Conservation of Natural Habitats and of Wild Fauna and Flora''. They are to protect the 220 habitats and ap ...

(SAC) - These are prime wildlife conservation areas in the country, considered to be important on a European as well as Irish level. *

Special Protection Area A Special Protection Area (SPA) is a designation under the European Union Directive on the Conservation of Wild Birds. Under the Directive, Member States of the European Union (EU) have a duty to safeguard the habitats of migratory birds and cert ...

(SPA) - Classified under the EU Birds Directive for the protection of endangered species of wild birds. *

Natural Heritage Area Natural Heritage Area () is a conservation designation denoting a protected area in Ireland. The Wildlife (Amendment) Act 2000 makes legal provision for the designation and protection of a national network of Natural Heritage Areas (NHAs). The de ...

(NHA) - This is an area considered important for the habitats present or which holds species of plants and animals whose habitat needs protection. The following areas of ecological significance are located either on or adjacent to County Mayo's offshore islands. The five major inland lakes listed as SPAs are also included, and are shown in ''italics'' in the list below. Puffin Latrabjarg Iceland

Special areas of conservation

*Mullet/Blacksod Bay Complex *West Connacht Coast *Erris Head *Inishkea Islands *Duvillaun Islands *Broadhaven Bay *Killala Bay/Moy Estuary *Croaghaun/Slievemore *Achill Head *Keel Machair/Menaun Cliffs *Doogort Machair/Lough Doo *Clew Bay Complex *Corraun Plateau *Lough Gall Bog *Clare Island Cliffs

Special protection areas

''Italics'' indicates that the SPA is an inland lake *Blacksod Bay/Broadhaven Bay *Inishglora and Inishkeeragh *Inishkea Islands *Duvillaun Islands *Stags of Broad Haven *Illanmaster *Killala Bay/Moy Estuary *Doogort Machair *Bills Rocks *Clare Island *Mullet Peninsula *Termoncarragh Lake & Annagh Machair *''Lough Mask'' *''Lough Conn & Lough Cullin'' *''Lough Carra'' *''Carrowmore Lake''

Natural heritage areas

* Tullaghan Bay & Bog * Doogort East Bog * Sraheens Bog

Proposed natural heritage areas

*Killala Bay/Moy Estuary *Glenamoy Bog Complex *Stags Of Broadhaven *Broadhaven Bay *Erris Head *Eagle Island *Mullet/Blacksod Bay Complex *Inishglora & Inishkeeragh *Inishkea Islands *Duvillaun Islands *Croaghaun/Slievemore *Doogort Machair/Lough Doo *Inishgalloon *Keel Machair/Menaun Cliffs *Corraun Plateau *Lough Gall Bog *Bills Rocks *Clare Island *Clew Bay Complex *Mweelaun Island *Caher Island *Ballybeg Island *Inishturk *Inishdalla *Frehill Island *Inishdegil Islands

Island index

File:Achill Island in inset - County Mayo.svg,

File:Clare Island in inset with Achill - County Mayo.svg,

File:Inishturk (with inset) - County Mayo.svg,

File:Inishkea North (with inset) - County Mayo.svg, Inishkea North File:Inishkea South (with inset) - County Mayo.svg, Inishkea South File:Achillbeg in inset with Achill - County Mayo.svg,

Achillbeg Acaill Bheag (Achillbeg) is a small island in County Mayo, Ireland, just off the southern tip of Achill Island. Etymology Its name means ''Little Achill''. History Acaill Bheag was evacuated in 1965 and the inhabitants were settled on ...

File:Annagh Island in inset with Achill - County Mayo.svg, Annagh Island File:Caher Island (with inset) - County Mayo.svg,

Caher Island Caher Island (''Cathair na Naomh'' in Irish), an uninhabited island off the coast of County Mayo in Ireland, is situated between the larger Clare Island and Inishturk. Etymology ''Cathair na Naomh'' in Irish means the ''City of the Saints''. ...

File:Barranagh Island (with inset) - County Mayo.svg, Barranagh Island File:Inishbiggle in inset with Achill - County Mayo.svg,

Inishbiggle Inishbiggle () is a small inhabited island off the coast of Ballycroy in County Mayo. Its name in Irish means "Vigil Island" Geography The island is situated between the northeast of Achill Island and the mainland, and is accessed by boat f ...

File:Eagle Island (with inset) - County Mayo.svg, Eagle Island File:Inishglora (with inset) - County Mayo.svg, Inishglora