Skibo Castle is the home of The Carnegie Club, a 6-year-old social club whose members enjoy access to two of the world's most luxurious resorts, as well as an elegant London pied-à-terre. For an annual fee of 3,525 pounds (roughly $5,000), Carnegie Clubbers earn the right to reserve rooms at Skibo Castle; Stapleford Park, a lavish English estate; and a charming London pied-à-terre, where guests are treated like British royalty. Stateside, The Carnegie Club has outposts called Cherokee Plantation, in South Carolina, and the recently opened Carnegie Abbey in Rhode Island, although both require a separate membership. But the story of The Carnegie Club begins with Skibo, a slice of Scottish paradise that Andrew Carnegie liked to describe as his own piece of "heaven on earth."

Strangely enough, the elegance of Skibo Castle has roots that stretch back to a ruthless viking. More than 1,000 years ago, Norse invaders led by Sigurd the Mighty established the first encampments here. Sigurd ruled by the sword, but by the late 12th century he and his troops had been banished.

A wealthy bishop moved in and built a castle on the remains of Schytherbolle (pronounced SKE-thur-bowl), the viking settlement that is said to have given Skibo its name.

The castle was passed down from bishop to bishop until the mid-1500s, when a nobleman named John Gray inherited the estate. For the next 400 years, as ownership bounced from one family to another, the castle drifted into disrepair.

Enter Andrew Carnegie, the son of a Scottish weaver, who had moved to the United States at age 13 and, by the time he turned 30, amassed an unfathomable fortune. Carnegie could have bought a vacation home anywhere he pleased. But he settled on Skibo, near the northernmost tip of his homeland, where the climate was unusually warm and dry (for Scotland, that is).

It's easy to understand Skibo's appeal. It stood on thousands of acres of unscarred hunting and fishing grounds. From the castle gates, the land unfolded into ribbons of green. There were glorious streams overflowing with salmon, placid duck ponds, and a soothing view of the Dornoch Firth, an ice-blue inlet from the sea.

Carnegie bought Skibo for 85,000 pounds (around $120,000), but poured another million-plus pounds into improvements. He added rooms (the castle now has more than 200), added windows (there are 400 of those), and built a waterfall in the garden so he could listen to it babble. He installed a game room, a smoking room, a billiard room, a swimming pool. He built a nine-hole golf course that wraps around the castle, the fingers of its fairways visible from several upstairs rooms.