For 40 years, Swedes had steadfastly refused to abandon left-hand driving, despite pressure from lobby groups such as Motormännen. With Europe opening up for travel, the motorist members' organisation wanted Sweden to follow its Nordic neighbours and most of mainland Europe in driving on the right-hand side of the road.
However, the majority of Swedes feared driving on the opposite side of the road would be more dangerous and disruptive. In a 1955 referendum, 83 percent of Swedes voted against change. However, swayed by growth in the car industry, the Swedish parliament voted through reform just eight years later.
September 3rd 1967 was the date when Sweden would change over to right-hand driving. A four-year campaign was started to win hearts and minds with a name and logo created for the big day - Dagen Höger, or the right day.
Elisabeth Edberg, a reporter at Swedish Radio's traffic department, tells Radio Sweden that the H logo appeared everywhere back then.
It was on car stickers and on the back of milk cartons. There was even Dagen Höger his and hers underwear. There was even a song, 'Håll dig till höger, Svensson,' which was very catchy and popular."
Edberg says that the second part of the campaign focused on the facts, alerting people to what was going to happen on the day of the switchover.
All non-essential traffic was ordered off the roads, from 10 am on Saturday in several places including Stockholm, to give the thousands of volunteers deployed around the country time to remove the plastic bags covering the thousands of new traffic lights, road signs, and bus stops.
Then at 4:50 am, all vehicles were ordered to stop, move slowly to the opposite side, and wait. Ten minutes later, the all-clear was given for traffic to start moving on the right-hand side of the road.
Anders Odéen was 19 years old on Dagen H. He remembers staying up so he could be the first to drive his VW Beetle on the right-hand side of the bridge from the island of Lidingö into central Stockholm.
Myself and two friends drank coffee and coca-cola to stay awake. We wanted to be the first to drive over the Lidingö bridge. When we got there, someone had beaten us to it so we were second. But it was a great moment. We went into central Stockholm and I remember how everyone was driving very carefully."
Anders, a veteran-car enthusiast, has lovingly restored an exact replica of the car he drove that day. He will be driving it again this Sunday at 5 am, along with 100 other cars from 1967 and earlier, in a reconstruction of Dagen Höger.