Why is the UK the only country to drive on the left?

It isn’t. Roughly a third of the world’s population—in about 75 countries and territories—drives on the left. Britain’s left-side rule stems from centuries-old practice (keeping to the left so right-handed travelers kept their sword arm toward oncoming traffic), later formalized in law, while much of Europe and the Americas standardized on the right under influences from the French Revolution/Napoleon and early U.S. road rules. The UK remains one of a minority in Europe to keep left, but it is far from alone globally.

The historical roots of left-side travel in Britain

The norm of keeping left in Britain predates motor vehicles by centuries. In crowded medieval streets, right-handed riders and pedestrians preferred to keep left so their dominant hand faced oncoming strangers—a practical safety choice in an era of blades and carts. As London traffic grew, authorities issued local rules—famously on London Bridge in the early 18th century—directing travelers to keep left to reduce collisions. The convention was ultimately written into national law: the UK Highway Act of 1835 required drivers to keep to the left, cementing a custom that has persisted into the age of the car.

Why much of the world chose the right instead

Elsewhere, the political and technological tides flowed the other way. After the French Revolution, France moved to right-hand travel, and Napoleonic rule spread that standard across much of continental Europe. In the United States, large freight wagons steered from the left encouraged keeping to the right for better sightlines, and states passed keep-right laws from the late 1700s onward. As international travel and trade expanded in the 19th and 20th centuries, many countries aligned with their neighbors’ practice—often switching sides—to simplify cross-border movement.

Key milestones that made Britain a left-driving country

These developments established and preserved left-side travel in Britain, long before cars appeared.

• Medieval and early-modern custom: Travelers kept left to keep their right (weapon) hand toward oncoming traffic.
• 18th-century local regulations: London authorities directed left-side movement in busy places such as London Bridge.
• 1835: The Highway Act mandated keeping to the left across England and Wales, creating a clear national rule.
• Imperial era: British colonial administration exported left-side driving to parts of Africa, Asia, the Caribbean, and Oceania.

Together, long-standing habits, urban management, and the codifying power of statute—and later, imperial standardization—fixed the UK’s left-side rule.

Where else drives on the left today

While Europe is mostly right-driving, left-side traffic is common across parts of Asia, Africa, and Oceania, and in many island nations. Below are representative examples, not a complete list.

• Europe: United Kingdom, Ireland, Cyprus, Malta; also the Channel Islands and Isle of Man (UK Crown Dependencies).
• Asia: Japan; India, Pakistan, Bangladesh, Sri Lanka, Nepal, Bhutan; Indonesia, Malaysia, Singapore, Thailand, Brunei; Hong Kong and Macau (though mainland China drives on the right).
• Africa: South Africa and most southern African neighbors (Botswana, Namibia, Lesotho, Eswatini, Zimbabwe, Zambia, Mozambique); East Africa’s Kenya, Tanzania, Uganda; island states Mauritius and Seychelles.
• Oceania: Australia, New Zealand, Papua New Guinea, Fiji, Solomon Islands, Samoa, Tonga (plus several smaller Pacific territories).
• Caribbean and Americas: Jamaica, Barbados, Bahamas, Trinidad and Tobago, Saint Lucia, Saint Vincent and the Grenadines, Grenada, Antigua and Barbuda, Dominica; in South America, Guyana and Suriname.

In total, left-side driving encompasses a broad swath of the former British Empire plus Japan, Thailand, Indonesia and others—reflecting a blend of colonial legacies and independent choices.

Countries that switched sides—and why

Many nations changed sides in the 20th century to harmonize with neighbors, improve safety, or accommodate trade and vehicle supply. These high-profile shifts show how geopolitics and practicalities shape road rules.

• Sweden (1967): Switched from left to right in a meticulously planned “Dagen H” to align with continental Europe.
• Iceland (1968): Moved from left to right, following regional norms and vehicle market realities.
• Myanmar (1970): Shifted from left to right by decree; many vehicles still have right-hand-drive layouts, creating challenges.
• Nigeria (1972) and Ghana (1974): Former British colonies that changed to the right to match West African neighbors.
• Okinawa, Japan (1978): After postwar right-side driving under U.S. administration, reverted to Japan’s left in the “730 Switch.”
• Samoa (2009): Switched from right to left to align with Australia, New Zealand, and the dominant flow of affordable right-hand-drive vehicle imports.

These transitions were often massive national operations—repainting roads, turning signs, retraining drivers, and reconfiguring intersections—undertaken to reduce cross-border friction and standardize vehicle fleets.

Practical effects: vehicles, borders, and design

Driving side influences the entire transport ecosystem. Left-driving countries use right-hand-drive vehicles, design roundabouts to flow clockwise, and place road signs and mirrors accordingly. Crossings between left- and right-driving jurisdictions—such as between Hong Kong and mainland China, or via the Channel Tunnel between the UK and France—use grade-separated “crossover” interchanges or lane realignments to swap sides safely. Vehicle import policies also track these norms: left-driving nations typically import right-hand-drive cars from markets like Japan, the UK, Australia, and India.

The bottom line

The UK isn’t unique in driving on the left; it’s part of a sizable global minority shaped by history. Britain’s left-hand rule grew from medieval practice and was codified in 1835, then carried worldwide through empire. Elsewhere, revolutionary France, Napoleonic influence, and early U.S. laws made right-hand driving dominant. Both systems persist today, each deeply embedded in regional networks, vehicle markets, and road design.

Summary

Britain drives on the left because of longstanding custom formalized by 19th-century law, not because it stands alone. About a third of the world follows the same pattern, largely due to British imperial legacies and independent choices in countries like Japan and Thailand, while most of Europe and the Americas drive on the right under French and U.S. influence. The divide endures because harmonizing with neighbors, infrastructure, and vehicle supply matters more than any inherent advantage of one side over the other.

Why does the US drive on the right and the UK on the left?

England (and the UK) drives on the left due to a long-standing tradition rooted in the need for right-handed riders and drivers to keep their sword or whip hands free for defense and control, which also made it safer to mount horses from the left. The United States adopted driving on the right because its dominant 18th-century transport involved large, heavy wagons and teams of horses, where the driver would sit on the left horse to control the team and avoid collisions, leading to a tradition of right-hand driving that predated Britain’s formal left-hand law.
 
Driving on the Left (England/UK)

• Pre-Automotive Era: Historically, most people are right-handed. For riders and knights, keeping to the left side of the road allowed their right hand, their dominant and sword hand, to be free to defend against potential attackers. 
• Mounting/Dismounting: It was safer to mount and dismount a horse from the left side of the road, which was the left-hand traffic side, rather than the middle of the road. 
• Official Adoption: Britain formalized this practice, making left-hand traffic the law in the 18th century, which was later reinforced by the Highway Act of 1835. 

Driving on the Right (United States)

• Post-Colonial Transition: After gaining independence, the US had a growing opposition to Old World customs and the British system of left-hand traffic. 
• Wagon and Horse Teams: The dominant form of long-distance transport in the US involved large, multi-horse wagons. Drivers would sit on the left-hand horse, often the rearmost of a team, to keep their right whip hand free to control the animals. 
• Safety and Practicality: Driving on the right allowed drivers to better judge the clearance between passing wagons, as they were seated to the left of the team, near the center of the road. 
• Dominant Practice: This practical shift in the US, driven by large freight wagons, established a tradition of right-hand driving that was distinct from Britain’s. 

Was the US ever a left-driving country?

The first keep-right law for driving in the United States was passed in 1792 and applied to the Philadelphia and Lancaster Turnpike. Massachusetts formalized RHT in 1821. However, the National Road was LHT until 1850, “long after the rest of the country had settled on the keep-right convention”.

Why is England the only country that drives on the left?

Keeping left only became a rule of the road and a legal requirement when there was an increase in horse-drawn traffic. Riding on the left was made mandatory in 1756 for travellers using London Bridge, in 1772 for towns in Scotland and in 1835 for all roads in Great Britain and Ireland.

Why do British people drive in the left side of the road?

It Was Written into British Law
In 1773, as British roads became more developed and congested, the government brought in the General Highways Act, which stated that all horse riders, farmers, coachmen and lawless highwaymen must remain on the left side to avoid any nasty collisions, even before cars had been invented.