It is quite straightforward to envision driving in either the left or right direction; however, the concept of mixed-direction driving may seem rather unconventional. While this practice is virtually nonexistent today, numerous countries adhere to either left or right driving based on established traffic regulations, with vehicles typically designed or imported to align with these standards.
Approximately 30% of the world’s nations require left-side driving, while around 70% adhere to right-side driving.
This arrangement facilitates smoother and safer transportation. Below is an overview of several European nations that transitioned from left to right driving and the effects this had on their road systems and populations.
Spain
In 1918, Spain still operated under a hybrid driving system despite officially adopting Right-Hand Traffic (RHT). Drivers in Madrid continued to drive on the left until a national law was enacted in 1924, mandating all drivers to switch to RHT.
Italy
Italy began driving on the right in the 1890s, with the practice becoming compulsory under the 1912 highway code. While cities with trams were allowed to maintain left-side driving, by 1927, all vehicles in Italy were required to drive on the right.
Portugal
The transition in Portugal occurred simultaneously with Italy and its colonies. However, regions adjacent to countries that drove on the left, such as Portuguese East Africa (now Mozambique), were exempt from this change.
Austria
From 1921 to 1935, the Austrian regions of Vorarlberg, Tyrol, Carinthia, and parts of Salzburg shifted to right-side driving. Following Germany’s annexation of Austria in 1938, Hitler enforced an immediate transition for the remainder of the country, resulting in a complete switch to right-hand driving by that year.
