February 14, 1977, was the day when Swedish Radio opened its very first local radio stations in central and northern Sweden.
P4 Norrbotten, P4 Gävleborg, P4 Dalarna, P4 Västerbotten, P4 Värmland, P4 Västernorrland, and P4 Jämtland all began broadcasting on Valentine's Day, with the aim of bringing radio closer to the general public.
Another 18 channels covering the whole of Sweden were later added that year, when "ABBA: The Movie" was shown at cinemas and Princess Victoria was born.
Johannes Rosendahl, head of news at P4 Dalarna, speaks of the advantages local radio has over national news.
We are close to our listeners and we are independent," Rosendahl tells Radio Sweden.
He says there have been a great many changes and challenges over the four decades, with the internet, social media and fake news, but the essential ingredients stay the same.
What has not changed is that we have a very strong connection to our listeners. We are their friend," he says.
P4 Gävleborg celebrated its 40th anniversary with an outside broadcast at Hälsingland's museum in Hudiksvall.
Handing out red roses to the public, station manager Kerstin Carlsson says the importance of local radio news was underlined by the famous snow storm that hit Gävle in the late 90s.
In Gävle in 1998 we had so much snow in just a few hours that the city was almost closed. They made a survey of how many people were listening to the radio when the snow came and it was 98 per cent of the public in Gävle, because it was so important to get information and we were the fastest medium."
On Tuesday, Swedish Radio published a video celebrating the local radio channels. You can view it here.