Why Do Some Countries Drive on the Left?

3 min read · 3 steps · Updated 2 October 2026

In more than seventy countries and territories, people drive on the left. In most of the world, they drive on the right. Why didn't everyone just pick one side?

This is Countries Compared. Today: where the left and the right came from, and the countries that switched overnight.

Step by step

1. 

   The old days

   For most of history, travellers in Europe often kept to the left. A popular theory is that most people are right handed. On the left, a rider's right hand, or sword hand, faced oncoming traffic. Historians still debate how true that is. But keeping left was common, and Britain later made it law.

   So where did the right come from?

   One reason is wagons. In the United States in the late 1700s, big freight wagons were pulled by teams of horses, and the driver often sat on the left horse. To see oncoming wagons clearly, it made sense to pass on the left, which means driving on the right. In 1792, a road in Pennsylvania became one of the first with a keep right law.

   In Europe, France moved to the right after the revolution, and Napoleon's armies spread the habit across much of the continent. Countries that resisted Napoleon, like Britain, mostly stayed on the left.

   Done

2. 

   Came the empires

   Britain took driving on the left to its colonies. That's why India, Pakistan, Australia, South Africa, Kenya and Malaysia still drive on the left today. Japan never was a British colony, but it drives on the left too. Keeping left was already an old custom there, and British engineers who built its first railways ran the trains on the left as well.

   Done

3. 

   But some countries switched

   The most famous is Sweden. On the 3rd of September, 1967, the whole country moved from the left to the right, at five in the morning. It was called Dagen H, H day. Traffic stopped, every car changed lanes, and new signs went up overnight. Its neighbours already drove on the right, and most Swedish cars already had the steering wheel on the left.

   Done

Good to know

And it can go the other way. In 2009, Samoa switched from the right to the left. Why? Many of its people lived in Australia and New Zealand, and cheaper used cars from those countries already had the steering wheel on the right.

Today, roughly a third of the world's people live in countries that drive on the left. India alone makes up a huge part of that.

So does it matter which side is safer?

There's no clear proof that either side is safer. What matters is that everyone in one country does the same thing. The risky moments are at borders, and when tourists drive in a country with the other rule.

And some borders are tricky. Between Thailand and Laos, or Hong Kong and mainland China, drivers switch sides at the border, using roads that cross over.

In short: The side of the road isn't about logic. It's about history: horses, wagons, Napoleon, and empires.