Some countries drive on the left because Britain kept a horseman’s habit and then exported it through empire. In the pre-industrial era, riders kept their horses to the left so they could draw their swords. Napoleon’s conquests later pushed continental Europe onto the right, and the United States followed France rather than Britain. Britain’s own colonies took the opposite habit with them: India, Pakistan, Australia and the Republic of Ireland all still drive on the left today.
A pattern that outlived the horse
That split has proved durable. Around a third of the world still drives on the left, a pattern the RAC traces largely to two centuries of British influence. Ireland, Australia, New Zealand and several South Asian countries, among them India, Pakistan, Bangladesh and Sri Lanka, keep left alongside the UK. Much of Southeast Asia does too, Malaysia, Singapore, Thailand and Indonesia among them. So do South Africa, Kenya, Tanzania and Uganda in Africa, and Jamaica, Barbados, and Trinidad and Tobago in the Caribbean.
Most of the world drives on the right. Nearly all of Europe, the Americas and Asia fall on that side of the line. The United States, Canada and Mexico all drive on the right, and so does almost every country further south, Guyana and Suriname the only exceptions. France, Germany, Italy, Spain and the Nordic countries all keep right as well, leaving the UK, Malta and Ireland as Europe’s three holdouts on the left.
Britain made left-hand driving mandatory in 1835, and countries in its empire followed suit. Japan, never part of the British Empire, ended up on the same side anyway. Its habit of keeping left dates back to the Edo period, and it became more or less official in 1872, when Japan’s first railway opened with British technical aid.
What switching sides would actually take
Britain has looked at swapping to the right before, and the obstacles are less about habit than concrete. Road markings and signs would need replacing across the country, ready in advance of a single changeover day. One in ten motorway junctions would need digging up and rebuilding, too, because they are not built symmetrically. Slip roads built as deceleration lanes would suddenly be used for accelerating, and would need lengthening to match, while the reverse ramps would need shortening.
Drivers would need retraining too, particularly on roundabouts, which would suddenly run anticlockwise, and on left-hand turns, which would newly require cutting across oncoming traffic. Britain’s right-hand-drive cars would eventually give way to left-hand-drive ones, and buses would need their doors moved to the other side of the vehicle. Changing the country’s road signs from miles to kilometres alone was once put at about £750m, giving some sense of the scale of a full changeover.
Sweden’s changeover, minute by minute
Sweden is the country that shows what the switch looks like in practice. Its parliament voted for the change in 1963, having rejected it by a wide margin in a 1955 referendum, and spent years preparing before acting. Every road sign in the country was doubled up in advance, with the new right-hand-side signs covered until the day itself.
The change came at 5am on Sunday 3 September 1967. Private traffic was banned between 1am and 6am, all vehicles stopped completely at 4.50am, and a radio countdown carried the country to the moment itself. Urban speed limits were cut from 50 km/h to 40 km/h for a period afterwards. Sweden made no changes to its cars, though: most already had their steering wheel on the left, and the country’s neighbours already drove on the right. The government later put the cost of the whole exercise at £264m in 1969 money, or roughly £3.4bn today.
Why Britain has stuck with the left
Britain examined its own switch in the late 1960s, two years after Sweden’s, and its report rejected the idea on grounds of safety and cost. That was before the country joined the European Union and before the Channel Tunnel gave it a direct land link to the continent. Both have since made the case for matching the rest of Europe a little stronger.
Not every country has left the question alone. Samoa moved the other way, switching from driving on the right to driving on the left, easing the changeover in with a two-day bank holiday so its drivers had time to adjust.
