Driving on the left,custom.

Driving on the left-hand side of the road can be a hurdle for many Americans coming to the United Kingdom, much like asking for the “loo” or saying “I’ll have the Toad in the Hole.”

So, why do they do it, when traffic just across the channel would beget a head-on collision?

“It basically goes back to the days of horses and carts, and the types of horse-drawn transport mostly in use in each country,” said Steven Jukes, president of the Society for All British Road Enthusiasts.

Often wagon drivers sat in the cart on the right, where (assuming a right-handed driver) they could use a whip without hitting passengers in the back. Sticking to the left side of the road also allowed drivers to keep an eye on their inside wheels when passing oncoming carts, helping avoid collisions.

There’s also evidence to suggest that the Romans, who once ran amok in England, mostly kept to the left.

Much less likely, however, is the common notion that knights stuck left to keep their sword hand on the inside, where it could do damage to approaching unfriendly types.

Regardless, while the fortunes of war and kingdoms (mostly Napoleonic France) swayed drivers back to the right in much of the world (including the U.S.), the English on their island stuck to the left, and have ever since.

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