Approximately 35% of the world population drives on the left, and the countries that do are mostly old British colonies. This strange quirk perplexes the rest of the world, but there is a perfectly good reason. The practice far predates cars, according to The Telegraph. In fact, it goes back to the Middle Ages. In ye olden days, when traveling down a highway put you at risk of being attacked or robbed, traveling on the left was a matter of safety.

163 countries and territories drive on the right, including European mainland. In France, traditionally foot traffic had kept right, while carriage traffic kept left. Following the French Revolution, all traffic kept right. Following the Napoleonic Wars, the French imposed right-hand traffic on parts of Europe. During the colonial period, right-hand traffic was introduced by the French in New France, French West Africa, the Maghreb, French Indochina, the West Indies, French Guiana and the Réunion, among others.

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