Why Do Some Countries Drive on the Left and Others on the Right?

The short answer

There is no single inventor of left-hand or right-hand traffic. Different customs developed over centuries, long before motor vehicles. As road networks expanded, governments formalised rules so that drivers, riders and pedestrians could move more safely.

In Southeast Asia, the result is a fascinating mixture of British, French and Dutch historical influence, alongside decisions made by independent governments.

How did left-hand and right-hand travel begin?

Traffic conventions existed long before cars, motorcycles or modern road markings. People travelled on foot, horseback and in animal-drawn vehicles, and local customs helped determine how travellers passed one another.

One familiar theory suggests that right-handed horse riders preferred keeping left, leaving their dominant hand closer to an approaching traveller. It is a plausible explanation for some historical practices, but it should not be presented as a proven universal origin of left-hand traffic.

The design of horse-drawn wagons, where a driver sat or stood, the need to judge clearance when passing, and differences between local roads also influenced traffic practices. There was no single global rule.

How Britain established left-hand traffic

Britain gradually formalised its keep-left convention as road traffic increased. The Highway Act of 1835 established a general keep-left requirement for roads in Great Britain and Ireland. British administration later helped extend similar conventions to territories including Malaya and Singapore.

Once a convention becomes established, changing it affects road signs, junctions, vehicle design, driver training and public safety. That helps explain why many countries retained their inherited systems after independence.

Did Napoleon invent right-hand traffic?

Napoleon Bonaparte is frequently credited with making continental Europe drive on the right. The historical reality is more complicated: right-hand travel practices already existed before Napoleon came to power.

France before Napoleon

Travellers in Europe did not always follow the same road convention. During the late eighteenth century, French authorities increasingly formalised traffic arrangements. The French Revolution preceded Napoleons rule, so the development of right-hand practices should not be attributed entirely to one military leader.

Napoleonic expansion

Napoleons campaigns and the administrative changes associated with French influence are often connected with the wider adoption of right-hand traffic across continental Europe. However, claims about a universal personal order directing every conquered territory to drive on the right require stronger historical evidence than popular accounts provide.

Why Britain remained different

Britain maintained its own left-hand road convention. European countries subsequently developed different legal systems and transport networks. These differences were carried into the age of motor vehicles and, through colonial administration, influenced traffic patterns elsewhere.

The useful historical lesson is not that Napoleon invented a traffic rule, but that political influence, government regulation and established road customs all helped shape modern driving directions.

Why did colonial history matter?

Road conventions often followed the governments that administered them. British-controlled territories commonly adopted left-hand traffic, while French-influenced territories generally followed right-hand traffic. Former Dutch territories in Southeast Asia provide a particularly interesting exception to present-day European patterns: Indonesia still drives on the left.

These are historical influences, not universal rules. Countries could preserve, modify or replace inherited practices after independence.

Which side does each ASEAN country drive on?

Six ASEAN countries keep left, while five keep right. The following comparison describes the normal direction of road traffic, not the position of the steering wheel inside a vehicle.

• Keep left: Brunei Darussalam, Indonesia, Malaysia, Singapore, Thailand and Timor-Leste.
• Keep right: Cambodia, Lao PDR, Myanmar, Philippines and Viet Nam.

The history of all 11 ASEAN countries

Myanmar: a major change in 1970

Myanmar previously used left-hand traffic. In December 1970, the government switched traffic to the right. The change is especially notable because many vehicles continued to have right-hand steering wheels, which can complicate visibility and overtaking. Popular accounts suggest unusual motivations for the switch, but these explanations should not be treated as established fact.

The Philippines: an official change in 1945

Philippine Executive Order No. 34, signed on 10 March 1945, formally established right-hand traffic. Its stated reasons included alignment with international practices, vehicle import costs and the traffic practices of United States military drivers. This provides a documented example of a government deliberately changing the national rule.

How road traffic conventions developed

Why does this matter when driving across borders?

A road trip can involve more than a change of language, currency or road signs. Drivers crossing from Thailand into Lao PDR or Cambodia must also adjust from left-hand to right-hand traffic.

Pay attention at border crossings

Some border approaches use signs, lane markings, barriers or specially designed junctions to guide vehicles onto the correct side. Follow the actual road layout and instructions from local authorities rather than assuming every border crossing works the same way.

Turning and entering junctions

Drivers accustomed to one traffic direction may instinctively look toward the wrong side when entering a junction. Take extra care when turning, leaving parking areas and entering roundabouts. Check local signs and traffic flow before proceeding.

Steering-wheel position is a separate issue

A country may require vehicles to drive on the right even when some vehicles have their steering wheels on the right. Myanmar is a well-known example. Steering-wheel position can affect visibility during overtaking, but it does not determine the legal direction of road traffic.

Driving permission and vehicle entry

Driving on the same side of the road does not automatically mean your licence will be recognised. Licence validity, vehicle registration, insurance, border documents and entry permission are separate matters governed by applicable rules.

Always check current destination-country requirements before travelling. Historical information cannot replace official road signs or legal instructions.

Frequently asked questions