THE sight of the greenish-grey hump of Ailsa Craig rising out of the waves often stirs fond memories. This granite jewel of the Firth of Clyde has become a familiar landmark for generations of Scots visiting the Ayrshire coast on day trips and childhood holidays.

One of my favourite anecdotes comes from my mother who, on a coach tour some years back, recounts her fellow passengers marvelling at the unfolding scenery. A man pointed out the window and gasped: “Oh look, it’s the Bass Rock.”

To be fair, Ailsa Craig and its east-coast counterpart near North Berwick do bear some similarities – both are volcanic plugs and have thriving bird colonies – yet, when it comes to history and geology, each is as starkly different as a human fingerprint.

Two-thirds of the world’s curling stones are said to originate from Ailsa Craig – a tradition stretching back hundreds of years. The granite quarried here is a mixture of what is known as “common green” and “blue hone”. It is low in quartz, meaning it is less prone to fissures and cracks.

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Kays Curling in the East Ayrshire town of Mauchline has made curling stones for every Winter Olympic Games since 1924, with the exception of Salt Lake City in 2002.

Yet, this is only a small part of the Ailsa Craig story. Over the centuries, it has boasted a castle to help ward off Spanish invaders, been used as a prison and reputedly as a smuggling base, with illicit goods hidden in the caves.

Today, Ailsa Craig is a bird sanctuary, leased by the RSPB until 2050. It has the third largest gannet colony in Scotland, while other avian residents include puffins, guillemots and kittiwakes. If you want a closer peek, there are daily boat tours from Girvan aboard the MFV Glorious.

Ailsa Craig’s nickname “Paddy’s Milestone” comes from its location roughly halfway between Glasgow and Belfast – a heart-soaring sight for those catching the ferry home to Northern Ireland or returning to Scottish shores.

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While writing this short piece, I enjoyed perusing the many images of Ailsa Craig we have amassed in The Herald archives over the years. I chose this one – taken by our staff photographer Colin Mearns in 2005 – because I liked its ever-so-slightly mystical and ethereal feel.

The name Ailsa Craig is an anglicisation of the Gaelic, Aillse Creag, meaning “fairy rock”. Gazing upon it, you can see precisely why some ancient mariner might have coined this apt moniker.