Staff and guests had to be evacuated after a fire at Mar Lodge early on Monday.
Employees at the National Trust for Scotland property near Braemar found thick smoke in the front hall around 1am.
Around 20 guests and staff and their families were taken to safety in the nearby Stable Block.
Firefighters traced the source of the smoke to a faulty light fitting in the hall.
Guests were later allowed to return - there was no significant damage to the building.
Mar Lodge Estate’s operations manager David Frew said: “The fire was small and the quick actions of our staff and the Scottish Fire and Rescue Service ensured there was no danger of it spreading.
“We are very grateful indeed for their promptness and professionalism, as well as the good humour and forbearance of our guests.
“As to the cause of the minor fire, we will investigate the matter thoroughly.
“Our electrical systems were only just recently inspected and found to meet all required standards and we need to determine exactly what has happened and take steps to ensure there is no repetition.”