Dumfries House dates back to 1759 when it was completed by renowned architects the Adam brothers on behalf of William Dalrymple-Crichton, 5th Earl of Dumfries.
It remained in private hands until 2007 when the aristocrat and former racing driver John Bute put the stately home in Cumnock, East Ayrshire, on the market.
Much of its highly-valuable furniture had already been transported to a London auction room when a deal was secured to save the property and its contents for the nation at the 11th hour.
The Prince of Wales had led a successful £45 million purchase bid, including a £20 million contribution from the Prince’s Charities Foundation.
The remainder came from the Scottish Government and charities including The Monument Trust.
As well as preserving a part of Scotland’s heritage, it was hoped the project to renovate the A-listed house and open it to the public would be a driver for economic regeneration in the area.
Tasks included restoring furniture, building a new access road and ensuring the house met health and safety regulations.
The Palladian mansion is famed for its collection of furniture by master craftsman Thomas Chippendale, which was specially made for the house.
It opened to the public in 2008 and the estate has gone on to host everything from education programmes and fashion shows to fitness classes and weddings.
Charles, known as the Duke of Rothesay when in Scotland, is a regular visitor to Dumfries House and in 2014 the Queen opened the restored five-acre Queen Elizabeth Walled Gardens.
The Prince’s Trust and Dumfries House Education offer training in hospitality, sustainable building and woodland management for young people not in employment or education.
An engineering workshop on the estate is aimed at boosting science, technology, engineering and maths subjects among schoolchildren.
An outdoor residential centre has been built for visiting youth groups, while other attractions include a shop, cafe, maze and woodland walks.
The Dumfries House Outreach Programme has been involved in a number of community projects including the rejuvenation of New Cumnock Town Hall and the refurbishment of an open-air pool in the town.
Charles said in 2016: “When I first took on Dumfries House it was always my greatest ambition to do as much as possible for all the various communities surrounding the estate.
“Dumfries House has a very special place in my heart for all sorts of reasons and I look forward to working for many more years within this wider community and beyond in continued effort to do what I can to help in this part of Scotland.”
Dumfries House now employs more than 200 full-time and part-time staff across the house, estate and education and training programmes.
Each year about 24,000 people visit the 2,000-acre estate.
Notable visitors have included Irish President Michael D Higgins, while Aled Jones and Myleene Klass performed at the house for a special Classic FM broadcast last year.
Countryfile’s Matt Baker has enjoyed a tour, and designer Sir Paul Smith and model David Gandy were among the fashion industry figures who attended a conference hosted there in 2016.