In the past, Grenjadarstadur ( Adaldalur) was the manor of the county. The total area of its dwelling houses is about 775 m². The oldest part dates back to the early 19th century and in 1877 most of the houses were restored or renovated. At this time approximately 30 people lived at the farm, but in 1915 only 15 people were registered there.
The dwelling houses were abandoned in 1932 and in 1955 The National Museum took over and after a thorough restoration in 1955 a district folk museum was opened to the public in 1958.