In 1925, Czechoslovakia accepted the Paris convention and undertook to change to right-hand traffic "within a reasonable time frame".
In November 1938, parliament finally decided to change to right-hand traffic with effect from 1 May 1939.
In the final days there were daily reminders of the change in newspapers and large warnings were painted on the streets and on tramway cars.
Drivers adapted quickly although a total of 26 traffic accidents and one fatality on the day of the switch were reported in Prague.
After the creation of the Slovak State in March 1939, buses in the capital Bratislava were adapted, and the last roads in Slovakia switched to the new system in 1940/1941.