Find the O'Malley tomb in Clare Island Abbey, thought to be Grace O'Malley's burial place, under its rare medieval roof paintings

Climb Knockmore, the island's highest point at 462 metres, for views across Clew Bay's scattered islands

Walk out to the old Clare Island Lighthouse on the north cliffs, dark since 1965 and now a private guesthouse

Find the O'Malley coat of arms carved in the abbey, with the family motto 'Terra Marique Potens' — powerful on land and sea

Grace O'Malley ran Clew Bay as a sea power in the 16th century and is thought to be buried on Clare Island, in the Cistercian abbey founded in the 12th or 13th century, which keeps rare medieval roof paintings. The O'Malley arms are carved in the same building with the family motto, Terra Marique Potens — powerful on land and sea, which in her case was accurate. Behind the abbey, Knockmore rises to 462 metres, high enough to show you the whole scatter of islands in the bay she controlled.

Grace O'Malley's Clare Island

Climb Croagh Patrick mountain (764m) to the summit chapel

Find the site where Saint Patrick is said to have fasted for 40 days in the 5th century, giving the mountain its pilgrim tradition

Time your visit for Reek Sunday, the last Sunday in July, when anything from five to thirty thousand pilgrims climb the mountain, some barefoot

See the National Famine Memorial at Murrisk, John Behan's coffin ship of 1997, and the ruined abbey beside it

Croagh Patrick is a quartzite cone rising 764m straight out of Clew Bay, and the tradition holds that Patrick fasted on the summit for forty days in the 5th century. People have been walking up it ever since — on Reek Sunday, the last Sunday in July, anything from five to thirty thousand climb it in a single day, and some of them still do it barefoot. The scree on the final cone is the hard part, loose quartzite that moves under you. The round trip is about 7km and the chapel at the top has been there since 1905. Most pilgrims now start from Murrisk, beside the ruined Augustinian abbey the O'Malleys founded in 1457, and across the road stands the National Famine Memorial, John Behan's bronze coffin ship, unveiled by President Mary Robinson in July 1997.

Croagh Patrick: The Reek

Climb Mweelrea to 814m, the highest point in Connacht

Look down the length of Killary Harbour from the summit

Walk part of the horseshoe over Ben Bury or Ben Lugmore

Look into the cliff-lined corries cut into the south-eastern face

Mweelrea rises 814m straight above Killary Harbour and is the highest mountain in Connacht, at the heart of a horseshoe massif that takes in Ben Lugmore and Ben Bury. Its south-eastern side is cut into cliff-lined corries, and the geology of the Mweelrea Formation is entirely different from the Twelve Bens across the fjord. It is a long, pathless, serious day, and the view down the length of Killary, Ireland's best known fjord, is the payment.

Mweelrea: The Highest Mountain in Connacht

Drive the Doolough Valley road from Louisburgh, the way the starving walked in March 1849, between the Sheeffry Hills and Mweelrea with the lake below the road

Read the inscription on the Famine Memorial cross beside the road — the annual Famine Walk in spring retraces the nineteen kilometres to Delphi and back

Go on to the gates of Delphi Lodge, the hunting lodge where the officials were staying and where the people were turned back

Stop at the shore of Doolough and listen — no buildings the length of the valley, and nothing but wind and water

On 30 March 1849 two officials of the Westport Poor Law Union came to Louisburgh to inspect people receiving outdoor relief. The inspection did not take place, and the officials went on to Delphi Lodge, a hunting lodge nineteen kilometres south. The several hundred people who had gathered were told to present themselves at Delphi at seven the next morning if they wanted to keep their relief. They walked through the night in bad weather, and when they reached the lodge they were told they were not eligible and sent back. Seven bodies, women and children among them, were found on the roadside above Doo Lough; nine or ten more never reached home. Some accounts put the dead at around twenty, and local tradition puts it far higher.

The Doolough Tragedy: A Valley of the Dead

Walk the length of the village, about a kilometre and a half, through its three sections

Look at how the houses are built — better than nine in ten are single-roomed byre houses, the cattle wintered at one end and the family at the other

At the eastern end, find the sweathouse — a low beehive of stone, the Irish equivalent of a sauna, used against rheumatism

At the western end, find the Slievemore megalithic tomb, a Neolithic tomb of roughly five thousand years ago that has never been excavated

Find out why the families who left in the 1850s came back up here every summer until the 1940s

On the southern foothills of Slievemore on Achill Island, a line of ruined stone houses runs about a kilometre and a half east to west in three sections — Tuar, Tuar Riabhach and Faiche — with 137 houses recorded by the Ordnance Survey. The archaeology puts the settlement no earlier than about 1750, and it was lived in the year round under the rundale system, the summer booley pastures being elsewhere on the island at Annagh, Dirk, Keem Bay and Bunnowna. It was abandoned through the 1850s — hurried by the Famine but not caused by it alone, with poor harvests, thinning soil and rising rents behind it — and most of the families moved down to Dooagh on the coast. Then they kept coming back: their descendants drove cattle up here every summer and lived in the old houses until the 1940s, the last place in Ireland or Britain where booleying survived.

Slievemore Deserted Village: The Last Booley Village

Walk out to Moyteoge Head above Keem Bay and look down on the beach and the cliffs

Walk down to Keem Bay's horseshoe beach and find Moyteoge Head, where the shark fishery's lookouts are said to have watched for fins

Hike Croaghaun and look down its sheer northern cliffs — at 688m, the highest sea cliffs in Ireland

Look across from the Keem road to Achill Head, the westernmost point of the island

Achill Island is Ireland's largest island, joined to the mainland by a road bridge at Achill Sound. Its west end holds Keem Bay's Blue Flag beach — once the base for one of the world's best-recorded basking shark fisheries — and Croaghaun, whose 688m northern cliffs are the highest sea cliffs in Ireland and third-highest in Europe.

Achill: Keem Bay and the Deserted Village

Listen for corncrakes calling from the meadows in late spring and early summer

Walk out to the Cromwellian barracks guarding the harbour mouth

Look for grey seals hauled out around the island's shore

Take the ferry from Cleggan and walk one of the island's waymarked loops

Inishbofin lies eight kilometres off the Connemara coast and much of it is a Special Area of Conservation, designated for its corncrakes and its seals. The corncrake is one of the great losses of Irish farming — a bird that vanished from the mainland as silage replaced hay — and Inishbofin is one of the few places left where you can still hear one calling from a meadow at night. At the harbour mouth stands a Cromwellian fort, built on the site where local tradition says a Barbary corsair had a stronghold before it.

Inishbofin: Corncrakes, Seals and Cromwell's Barracks

Take part in an Irish-language workshop on Arranmore, the largest inhabited island in Donegal and a stronghold of Ulster Irish

Visit Arranmore Lighthouse at the island's north-west tip, first established in 1798

Go sea angling from the island's harbour at Leabgarrow

Take the ferry from Burtonport, and walk or cycle the island road round the cliffs on the western side

Arranmore is the largest inhabited island in Donegal and one of the strongholds of Ulster Irish — a dialect distinct enough from the Irish of Connacht and Munster that learners notice it immediately. The island runs Irish-language workshops, which is the honest way to spend a few days here rather than just looking at it. The lighthouse at the north-west tip was first established in 1798, and the ferry runs from Burtonport on the mainland.

Arranmore: Donegal's Gaeltacht Island

Find the Tetrapod Trackway on Valentia's northeast coast — footprints left by an early four-legged vertebrate 385 million years ago, among the oldest tracks of their kind anywhere

Go up to the slate quarry at Dohilla — a working quarry, so check access — which supplied slate for the Houses of Parliament and Westminster Abbey

Visit Valentia Island Lighthouse at Cromwell Point, guarding the northern entrance to Valentia Harbour

Cross the bridge from Portmagee, one of only two ways to reach Valentia along with the summer car ferry

About 385 million years ago something with four legs walked across wet mud on what is now the north-east coast of Valentia, and the prints set. They are among the oldest tracks of a land vertebrate found anywhere on Earth — the moment life came out of the water, recorded in stone you can stand beside. The island has a second seam of history in it: the slate quarry at Dohilla, opened in 1816, shut for most of the 20th century and worked again since the 1990s, supplied the roofs of the Houses of Parliament and Westminster Abbey. You reach Valentia by the bridge at Portmagee or, in summer, the car ferry.