THE Dowager Duchess of Devonshire is to receive a lifetime achievement award for her contribution to tourism – only days before her 90th birthday.

She has helped to transform Chatsworth House since the Second World War and will receive the honour to mark her achievements on Thursday at the county's first Excel Tourism Awards.

It is being handed over by Derbyshire's tourist board in recognition of her "key achievements in a long and distinguished career".

The last surviving of the famous Mitford sisters, she will be awarded the accolade to mark 55 years of responsibility for housekeeping at Chatsworth and other Devonshire properties.

David James, chief executive of Visit Peak District & Derbyshire, praised the efforts of the Dowager Duchess who will be 90 on March 31.

He said: "The Dowager Duchess, together with the late Duke, played such an important part in the success of Chatsworth over so many years that we felt it appropriate to recognise her. She is a wonderful ambassador, both for the Chatsworth itself, and for the Peak District and Derbyshire."

The Dowager Duchess helped to transform Chatsworth from a post-war estate crippled by death duties into the thriving business operation and tourist attraction it is today.

She will receive the accolade in the presence of her son and daughter-in-law, the 12th Duke and Duchess of Devonshire.

During her career, the Dowager Duchess has launched various enterprises at Chatsworth, principally the farm shop and other retail outlets. They now have a combined annual turnover of about £10m.

She helped to set up the popular family attraction, Chatsworth Farmyard and Adventure Playground, and has written books, ranging from the best-selling The House – A Portrait of Chatsworth, to Memories of Andrew Devonshire.

A mother-of-three, grandmother-of-eight and great-grandmother-of-17, she has been involved with many charities and organisations.

In the Queen's New Year's Honours List of 1999, she was awarded Dame Commander of the Royal Victorian Order for her work as a trustee of the Royal Collections Trust.

The Honourable Deborah Mitford is the youngest daughter of the 2nd Baron Redesdale.

She and her siblings – Pamela, Diana, Unity, and authors Jessica and Nancy – were prominent as the glamorous Mitford sisters during the pre and post-war years.

Well-known for her passion for country pursuits, the Dowager Duchess is interested in poultry and an avid Elvis fan, with a collection of memorabilia which includes a telephone from the Graceland gift shop.