Traveling on the left side of the road was a practice that started with the feudal societies of Western world, like the proto-British empire " back in the day, you never knew who'd you pass on the road, so best to keep your sword arm between you and them.
Read the full text here: http://mentalfloss.com/article/22735/how-do-countries-choose-which-side-they-drive#ixzz2I7HU06TV
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