In the UK, and some parts of Europe and Asia, motorists drive on the left side of the road. In the United States and France, drivers stick to the right. Why is this?
It turns out there isn’t any one answer.
The earliest explanation goes back to a time when roads were rife with bandits and wild animals in feudal Europe. Riding or driving a carriage on the left side of the road would have kept most people’s dominant hand, the right one, open to carry a weapon. So, most people stuck to the left side of the road, especially in England. This helped right-handed swordsmen keep their limbs intact and their heads on their shoulders should they ever meet an opponent.
On a slightly more rudimentary note, riding on the left side of the road ensured that a right-handed person’s sword-sheath wouldn’t constantly hit other people while they traveled. It’s also safer to mount and dismount a horse when you’re riding on the left side of the road, since a right-handed person finds it much easier to mount from the left side of a horse. For the same reason, it’s safer to mount and dismount at the edge of the road, rather than right in the middle of traffic.
Up until the late 18th century, however, nobody traveled much. It was too dangerous or too expensive. Because of this, road traffic was fairly light and there was no need to regulate it. By the late 1700s, however, as the world industrialized and travel became safer, regulation was needed.
Britain opted to pass a law that said all carriages and horsemen would have to drive on the left side of the road.
Naturally, Britain passed its driving regulations onto the hundreds of colonies she founded across the globe. Australia, New Zealand, South Africa, and India all still drive on the left side of the road, just like Britain does.
Some former British colonies and other left-inclined European countries have opted to change how they drive in order to cope with traffic from right-driving neighbors, though. Canada switched during the 1920s, and Sweden spent $120 million to make the switch in 1967.
Why Does the US Drive on the Right?
So, why does the United States drive on the right? The United States used to be a British colony, after all! What changed?
Well, you can blame 1700s economics and Henry T. Ford.
During the industrialization of the 1700s, farmers began to use massive “freight carriages” to haul their products. These carriages needed to be pulled by several teams of horses, and had no driver’s seat. Instead, the driver would sit on the left rear horse, where he could keep his right arm free to direct his team of horses. Because of this, everyone would pass on the left of the driver so he could focus on steering the team out of the way of oncoming traffic. To make this easier, these huge freight wagons began driving on the right side of the road in the United States, and other horse-drawn traffic quickly followed suit to avoid collisions.
When Henry T. Ford began to mass-produce his Model T with a left-positioned steering wheel, this was the final coffin in the old left-driving ways of the United States. Many people already drove on the right side of the road because of the carriage etiquette put in place by freight wagons.
Ford’s intent with the left-positioned steering wheel was, in fact, to keep women safer. It was assumed that women would be passengers, and so the safest thing for them would be to exit the car at the curb on the left, out of traffic. In 1909, a Ford brochure also explained that putting the driver on the left side of the car also helped the driver see oncoming traffic easier, and would help with judging left turns and other distances.
It’s pretty much impossible to drive on the left side of the road with a left-positioned steering wheel. So, thanks to Henry Ford, cars in the US have been keeping right ever since.