The Aran Islands--Inishmore (also known as Araínn), Inishmaan, and Inisheer--lie off the West coast of Ireland near Counties Clare and Galway.
The three islands have provided the settings for such works as John Millington Synge's Riders to the Sea, and The Aran Islands; several of Liam O'Flaherty's novels; Robert Flaherty's film Man of Aran; and Martin MacDonagh's trilogy of plays, including The Cripple of Inishmaan.
The Arans are scarcely islands: more like rocks with minimal soil cover.
Just about everything is made of rock, from the prehistoric fortresses such as the massive Dun Aengus
to the thousands of walls dividing the small islands into tiny plots of land or rock.
Most of the Aran men have always been fishermen, but fishing around the Aran cliffs
in the curraghs (small, wood-frame, tarred canvas boats)
has always been extremely dangerous. So many men are lost to the sea that Inishmore's most famous graveyard, in use since the 6th century, is not yet full and is still used today.
The islands are part of the Gaeltacht, the area in Western Ireland in which Irish is still a living language. Often known elsewhere as "Gaelic" but nearly always called "Irish" in Ireland, this is an ancient Celtic language, closely related to Scots Gaelic and Manx, more distantly related to Welsh, Cornish, and Breton, and scarcely related at all to English. Most islanders can speak English today, but they still speak mostly Irish among themselves.
Here is a site with information about, and texts in, the Irish language.
Until quite recently, life on the islands was not so terribly different from that which Pegeen Mike (1907) or Cripple Billy (1934), or, for that matter, their great-great-grandparents, would have known. Conveniences such as electricity and gasoline have only come to the islands within the past thirty years. A 1996 National Geographic article said that the Arans have changed "more in the past 25 years than in all the centuries before." Thus, The Playboy of the Western World and The Cripple of Inishmaan take place in what was, to a large extent, an almost timeless world.