You can master the art of packing lightly, you can learn the tricks to defeat jet lag, but there’s one thing that can throw even the most seasoned travelers for a loop: the direction of traffic. If you’ve visited the United Kingdom, or any countries that were formerly under the control of the British, you probably noticed that cars drive on the left side of the road, which is the opposite of what Americans are used to. Actually, about 25 percent of territories and countries drive on the left. Which is a substantial portion of the world.
Which countries drive on the left? And how did that decision come about? Here we’ll take a look at some of the historical circumstances that led to the left vs. right divide. You can see a full list of the territories and countries that drive on the left here.
Britain’s Left-Driving Empire
We can’t pinpoint exactly when and where certain countries first collectively decided to drive (or, more accurately, ride) on the left side of the road. The main theory is that it started in Britain and spread with the British Empire.
Historian and author Sean Stewart, who founded Berlin Historical Walks, describes the prevailing explanation for left-hand driving.
“The old story goes that people should walk or ride on the left, as in the U.K., because that way the sword arm (the right arm) will pass by the sword arm of the person coming at you the other way,” Stewart says.
In other words, it was a strategic, defensive move to put horse traffic on the left. The British then colonized much of the world, bringing their left-hand riding with them. The horses were eventually replaced by cars, but the traffic norms were already set. And the rest is history.
Today, India, Australia, New Zealand, Hong Kong, Malaysia, Kenya, Ireland, South Africa and many more countries that were at one time a colony of Britain still drive on the left.
The Other Lefties
There are also a handful of countries and territories that were never part of Britain, and yet people still drive on the left. For some, there’s a logical explanation for why they have left-hand driving. In Japan, for instance, the country’s first railway line was built during the Edo Period (early 17th-mid 19th centuries) with assistance from the British, who designed it with their home country’s left-hand driving in mind. The rules of the road for cars were modeled after the flow of train traffic.
Indonesia drives on the left because it was a Dutch colony and the Netherlands used to have left-hand driving. But when Napoleon invaded the Netherlands, the Dutch switched to driving on the right. Former Dutch colonies, like Indonesia and Guyana, didn’t follow suit.
Then there’s Thailand, which drives on the left for no apparent reason. It wasn’t a British or Dutch colony, and there doesn’t seem to be any explanation out there as to why they drive on the left.
The “Right Side” Of History
So that leaves nearly 75 percent of the world driving on the right side of the road, and there’s a theory for how that began as well. In the 18th century, the rise of freight wagons drawn by multiple horses meant drivers had to sit behind the horses on the left, in order to use the whip with their right hand. For safety reasons, it made more sense for them to be closer to the center of the road, and so right-hand driving was born.
Stewart says this explanation isn’t foolproof: “The problem, in my view, is that this situation also existed in the U.K.”
So why didn’t that have an effect on the British? The simple answer is, these theories for why certain countries drive on the right vs. the left don’t tell the whole story. According to Stewart, there’s more to it than that.
“It comes down to luck, chance, habit and custom,” Stewart says.
The United States, of course, drives on the right. Canada didn’t originally but switched to match U.S. traffic flow. Most of Europe now drives on the right as well. As the story goes, the aristocracy in France used to drive on the left side, forcing the peasants over to the right, but after the French Revolution, aristocrats moved to the right to blend in. Right-hand driving became the norm in France, and when Napoleon conquered a large portion of Europe, he brought these road rules with him. Today, former French colonies the world over still drive on the right side of the road.
Making The Switch
What happens when you drive from a left-hand driving country to a right-hand one, or vice versa? Many of the countries that drive on the left are islands, so that makes it easy. But for those with opposite-driving neighbors, different countries handle it in various ways. Some places, like Thailand, simply use a stoplight to switch the direction of traffic. Others, like Macau, built elaborate twisting ramps to facilitate side-switching. And in some places there is very little traffic, so just a sign does the trick.