Scotland's most imposing two Royal strongholds, the Castles of Edinburgh and Stirling, both stand on pedestals of rock formed by extinct volcanoes. Between them they preserve in stone the records of many of the most dramatic events in our nation's past. Edinburgh Castle, somthing of a frontier fortress, often witnessed the more violent events of history, but now enjoys the privilege of housing the royal regalia and welcomes the largest number of visitors of all Scotland's castles. Stirling Castle has been described as the Key to the Kingdom, and so it proved in 1314 when King Robert the Bruce defeated the chivalry of England at Bannockburn nearby. The Earl of Cassellis in the 1770's commissioned Robert Adam to transform his mansion on the cliffs of Culzean into one of the masterpieces of his genius. With its surrounding country park Culzean Castle is today a jewel of the National Trust for Scotland. Dunrobin Castle is a Ducal mansion of astonishing magnificence. It was originally a mediaeval castle, transformed in the mid-19th century into what might be mistaken for a French Chateau. This sumptuous home has been lovingly furnished by its fabulously rich owners and is now filled with lavish treasures for visitors to enjoy. The Scots Baronial style of architecture evolved during the middle ages and the Castles of Glamis, in Angus, is perhaps its supreme masterpiece. Home to successive generations of the ancient family of Lyon, this was the childhood home of HRH the Queen Mother.