Oighreachdan na h-Alba/Great Estates

For more than 500 years, Inveraray Castle has housed the chieftain of one of the world's best-known family clans, the Clan Campbell. It is now the home to the 13th Duke of Argyll, His Grace Torquhil Ian Campbell, and his young family. Visited by thousands every year, the castle was the stand-in for "Duneagle" in the "Downton Abbey" Christmas episode.

The 70-room Kincardine Castle is home to only two people, Andrew and Nicky Bradford. In a little over a century, the castle and its surrounding 3,000-acre estate have gone from being a trifling extravagance for its fabulously rich owners to presenting a passionate but ongoing struggle to keep it afloat for its present-day occupants.

Uncover myths and legends of mysterious Rosslyn Chapel, where part of The Di Vinci Code was filmed. Many believe it to be home to the Holy Grail, the skull of St. Matthew or John the Baptist or even of Jesus Christ. The program seeks answers and makes breathtaking discoveries.