Ailsa Craig (Gaelic: Creag Ealasaid) is an uninhabited island in the Firth of Clyde, 9 miles off the coast of Ayrshire. It measures about 3⁄4 of a mile north-south by ½ a mile east-west, and rises abruptly to 1120 ft (340 m). Its distinctive pyramid can be seen from afar in good weather. It's nowadays a birdlife reserve, though its granite is still quarried to make curling stones.

Understand

Approaching Ailsa Craig

Ailsa Craig is a pluton, a volcanic upwelling from about 60 million years ago, along with similar hills on the nearby island of Arran. Typically a pluton has no erupting volcano, but magma wells up and shoulders aside pre-existing rock. It then cools very slowly into coarse-grained granite that is hard-wearing, so it persists long after surrounding features have eroded away. Plutons have formed throughout Earth's existence and this one arose in the Palaeogene, formerly called the Early Tertiary. In that period the continents came close to their present positions, the global climate cooled, and dinosaurs suffered mass extinction to be replaced by mammals. Then followed the ice ages, which scraped and polished the surface of Ailsa Craig, and transported boulders from it as far away as Pembroke and Donegal. Any Stone Age person stranded amid the frozen wastes would be sure to think: "Hey, what a colossal ice rink and helluva curling stone".

The island has fresh water but almost no topsoil, and it's a long way to bring sheep for grazing, so only intermittently was it inhabited. Around 1400 it was owned by the Cluniac monks of Crossraguel, and has been a bolthole for fugitives and landing-beach for fishermen and pirates. It's always been a nesting place for seabirds and stop-off for migratory flocks: the solan geese were hunted into modern times. Yet this remote spot once had a gasworks and two railways.

From the mid-19th century Ailsa Craig was quarried for its distinctive granite "Ailsite", a form of riebeckite (formula Na₂(Fe²⁺₃Fe³⁺₂)Si₈O₂₂(OH)₂, since you were wondering). The floor of the Chapel of the Thistle in St Giles Cathedral Edinburgh is an example of Ailsite granite. The railways - really just wagon haulways - were built then, and the visiting freighters brought rats, which set about the island bird population. A lighthouse was built by the Stevensons in 1886, and automated in 1990, when its keepers the last island residents left. Ailsa Craig has no safe all-weather harbour and the quarry was unprofitable for mass extraction of building stone, but found a niche use as a source of curling stones.

In the background, they left a morsel

Curling is the sport of sliding stone bowls over ice towards a target area, and the curl is induced by the spin of the bowl as it travels, offset by brushing the ice to speed and straighten its path. Curling emerged in the 16th century in Scotland and the Netherlands; it's not agreed which was first, but both had freezing cold winters and strong trading links. At first, any hefty flat-based stone would serve, then the sport was regularised and a handle became standard. Ailsa Craig is the traditional source, fashioned into stones by Kays in Mauchline near Ayr. Trefor quarry on the Llŷn Peninsula in Wales exports stone to the Canada Curling Company. The stone has a concave base, so all the contact with the ice is on its rim. The ice is not flat but "pebbled" by frozen droplets of water for a faster running surface. This means that the contact is highly concentrated, so a completely impervious stone is necessary, otherwise water would be forced in at microscopic level, would then freeze and crack the structure, and the stone would soon become pitted and unusable. Kays only quarry once every few years, taking 2000-ton batches of three Ailsite varieties (green, blue, and a little bit of red) back to the mainland for storage until required for manufacture. These amounts aren't going to diminish the island any time soon.

The island is now a bird sanctuary managed by the Royal Society for the Protection of Birds (RSPB). In 1991 the rats were eradicated by poison: they had been especially damaging to puffins, which nest in easily accessible burrows, where eggs and chicks are unguarded while the adults fish. The rabbits are also an introduced species but are much less damaging and their presence is tolerated. Puffins soon re-colonised the island, and all species showed a rebound in numbers.

Get in

There are no scheduled ferries, and most visitors get here on a boat trip. Most trips are non-landing, circumnavigating to view the wildlife. Ailsa Craig is also within sea-kayaking range, but you're nine miles out, think about the changing conditions and the getting back.

Girvan is the usual point of departure for trips, see that page for details. McCrindle the main boat operator advertises year-round sailings. In reality, the weather and lack of customers make trips unlikely in winter.

Cruises of the west coast and Hebrides sometimes approach Ailsa Craig. One example is the Waverley, the world's last sea-going paddle steamer, which ranges around the Firth of Clyde in summer. This elderly vessel has had long spells hospitalised for repair, and it's a wonder she keeps going.

The landing jetty on Ailsa Craig is on the sheltered east side, just north of the lighthouse.

Get around

Walk everywhere. You need stout boots.

See

• The railway ascends from the landing area to a winding station, then forks to the lighthouse or to the gasworks. It's 3-foot gauge, with the initial gradient cable-hauled and the upper sections worked by horse or hand. The gasworks stand in what had been a kailyard, with a stone wall to keep goats off the crops. Until 1911 coal-gas was made to power the lighthouse and the compressors which piped air to the island's north and south foghorns - some stretches of pipeline remain. Foghorns were discontinued in 1987.
• 1 Ailsa Lighthouse was completed in 1886. It's near the landing jetty on the only stretch of flat land, so it can be seen from the Ayrshire coast and inshore channel, but not from out in the Irish Sea. It used oil- then gas-burning lamps, which in 1911 were replaced by incandescent lighting. It was connected by telegraph in 1935: until then the keepers relied on carrier pigeons. On stormy nights when pigeons couldn't fly, urgent messages (for instance to send a doctor) were indicated by signal fires. The lighthouse remains active: it was automated in 1990 and converted to solar power in 2001. Attempts to sell off the keepers' cottage for exclusive accommodation have so far come to nothing, as has a far-fetched plan to develop an outpost of Trump Turnberry Resort here.
• The quarry railway is now only marked by a trackbed round the south end of the island. It was a fairly basic horse-drawn haulway for tubs of stone.
• 2 Ailsa Castle is a typical Borders turret of circa 1500 that finds itself somehow marooned here. It was refurbished in the 1580s when war with Spain was expected. In the event, a string of calamities drove the 1588 Spanish Armada right around the tip of Scotland to the Atlantic coast, but none of the stricken ships tried to land here. There were attempts to use the island as a bolthole for Catholic fugitives of persecution (which didn't end well for the Catholics) and as a forward base for another Spanish incursion (likewise a fiasco played out elsewhere). The castle ruins stand 39 ft (12 m) tall, approached by the steep path towards the summit.
• 3 The cairn marks the island summit, with breezy views west towards Mull of Kintyre (with Sanda Island just off it) and the Antrim coast (with Rathlin island just north).

Do

The castle, with lighthouse below

Wildlife spotting: the skies are especially full of sea birds during the nesting season of spring and early summer.

Eat and drink

Bring everything you need with you, as there is no food or drink on the island.

Sleep

There is no accommodation on the island, and camping is not permitted.

Stay safe

Boat trips are generally open or only partly covered, so you need warm, windproof and waterproof clothing, at any time of year.

The cliffs are dangerous and the ground nearby is often slippery from drizzle and bird-poo.

Connect

Wild flowers near the summit

As of Oct 2022, the island has no mobile signal. Consider leaving your phone somewhere safe ashore, rather than risk a soaking or breakage in a stumble.

Go next

• Girvan is probably where your boat trip will return you. It retains its character as a fishing village rather than a "Costa Clyde" beach resort.
• Ayr is particularly associated with the poet Robert Burns, who grew up in Alloway 3 miles south. A further six miles south near Maybole is the ruin of Crossraguel Abbey, which once owned Ailsa Craig.
• Mauchline 12 miles east of Ayr is the home of Kay's, whose curling stones are sold world wide - reckon £300 for a new one, but you need a set, and think about the cost of postage. Robert Burns farmed awhiles unprofitably at Mauchline, as he did at Maybole and Tarbolton, but the only mementoes of those times are plaques and graves of his boozing companions and lovers.