BY DIANE W. STONEBACK

The Morning Call (Allentown, Pa.)

England's Highclere Castle, the real-life Downton Abbey, has a past that's every bit as colorful and riveting as the hit "Masterpiece" series filmed within its walls.

Besides serving as the main set for the hit PBS series that recently premiered its third season, this imposing landmark and the land it occupies has been home to generations of the Earls of Carnarvon since 1679.

"It's an amazing place to wake up in. I've never lost my sense of wonder for it," says Lady Fiona, the current Countess of Carnarvon, who lives at Highclere with her husband, the Eighth Earl of Carnarvon. She has written a book about the castle, which occupies a lofty hilltop in southern England and welcomes a limited number of visitors each year.

At the forefront of British high society for much of its history, the castle has sheltered some of Britain's most privileged celebrities (including a future king) and has its own hints of intrigue, World War I public service, a stunning link with ancient Egypt and the shadow of a pharaoh's curse. At times, threads of its reality have been woven into "Downton Abbey."

Watching all three seasons of "Downton" surely will stoke PBS fans' desire to visit the castle. Happily, they can tour the grounds where Robert, Lord Grantham, walks his Labrador retriever; enjoy the gardens where Violet, the Dowager Countess, sometimes takes tea; and see the main rooms where the lives of the Crawley family and servants unfold.

But the castle opens only for 70 days a year, and tour tickets are as hot as the PBS "Masterpiece" series.

In case you can't visit, or want to develop an appreciation for the castle's history before you go, read Lady Fiona's book, "Lady Almina and the Real Downton Abbey, The Lost Legacy of Highclere Castle" (Broadway Paperbacks, $15.99).

Lady Almina, wife of the Fifth Earl of Carnarvon, is believed to have been the illegitimate daughter of wealthy banker Sir Alfred de Rothschild and his French mistress. Like Lord Grantham's wife, Cora, her fortune not only kept a roof over the family's heads but also fueled a legendary lifestyle.

Her dowry paid off her future husband's already-substantial debts. It also included a guaranteed annual income for Lady Almina of more than $10.5 million per year, in today's dollars.