Eight multi-storey flats in Aberdeen have been awarded category A listed status for their architectural and historic interest.
Historic Environment Scotland said they are of "outstanding" importance.
HES has been consulting on their status since 2019.
The high-rises involved - built in the 1960s - are Gilcomstoun Land, Porthill Court, Seamount Court, Virginia Court, Marischal Court, Thistle Court, Hutcheon Court, and Greig Court.
Elizabeth McCrone, head of designations at HES, said: "Listing is a way of recognising buildings and structures that create Scotland's distinctive character, and through which we can discover more about the stories of our past.
"The Aberdeen flats tell us much about how the city and its architects responded to the challenges of housing large amounts of people in the city centre during the 1960s - a time of relative prosperity, low unemployment and optimism for the future.
"By designating and building these flats the Aberdeen City architects department were at the cutting edge of new thinking about town planning and housing."
She added: "Listing doesn't mean that a structure has to stay the same forever or remain in its original use. Rather, it means that there is a special interest that should be taken into account in the planning process."
The proposal to list the buildings came from Miles Glendinning, a professor of modern architecture at Edinburgh College of Art.
Prof Glendinning said: "I'm a great admirer of the granite city, and these buildings fit into its fabric, both in material - using granite in their construction - and in how they've been built into the historic and modern urban pattern.
"In architectural terms, these buildings stand out because architecturally and socially, they are a continuation of the civic-mindedness and pride of previous generations of great Aberdonians.
"They are also a social success, which for me is just as important as the architectural interest."
Guidance for residents about what listing means is being drafted.
They follow the so-called "Banana Flats" in Leith - made famous by Irvine Welsh's Trainspotting - which were awarded an A-listing in 2017.