'No' vote campaign poster. Translated it reads: "Keep left-hand traffic. Vote NO on 16/10."
A non-binding referendum on the introduction of right hand traffic was held in Sweden on 16 October 1955.
The voter turnout was 53.2%, and the suggestion failed by 15.5% against 82.9%. However, eight years later, in 1963, the Riksdag approved the change. The traffic in Sweden switched from driving on the left-hand side of the road to the right on 3 September 1967 (see Dagen H).