For motorists arriving in Dover by ferry and unacustomed to driving on the left , it ' s a worry ! This apprehension is heightened when , on leaving the ferry , a sign indicates ‘Drive on the left ' but the driver will follow the flow of cars vigilantly . Adapting to driving on the left is a real challenge , especially as the next test will be the roundabout . He has to get used to changing his reflexes quickly . In England , despite left-hand drive , vehicles have adopted a right-hand staering wheel , unlike in most other countries . This specificity has its origins in medieval traditions . For thousand of years , the roads were driven by horsemen , most of whom were right-handed , but carried their swords on their left legs . This made it easier for them to use their right hand to draw quickly for better defance or attack when encountering a malevolent individual . In fact , because of this tradition and for convenience , they ridden on the left , a practice that lasted until the eighteenth century . At the beginning of this era , first in the United States and then throughout the rest of the world , a new type of horse-drawn cart appeared , called the ‘Conestoga ' This buky cart was easier to handle if the coachman sat on the last animal at the front left , so as to keep his right hand free to handle the whipe . Right-hand traffic was the natural choice , as it was easier for the coachman to control the horses when crossing to the left , thus avoid the wheels of the two carriages colliding , and also providing better visibility . In the UK , the small roads made these ‘vehicles ' impractical and rare , so the habit of driving on the left was retained . A first British decree legislated in this direction in 1773 . As a result , for the United Kingdom and the British colonies , left-hand trafic continued . With the arrival of the motor car , right-hand drive was justified by the fact that the first cars had a brake consisting of a lever placed outside the bodywork , for the right hand . As for the steering wheel , it was placed in the centre , then to the left of the dashboard . As the handbrake moved to the centre of the car , the steering wheel shifted to the left to allow the driver to continue using the handbrake with his right hand . At the same time , the driver continued to drive on the right-hand side of the road , to better appreciate oncoming traffic . There is no particular advantage to driving one way or the other . Only 35% of the population drive on the left . The only advantage would be to harmonise these countries within the framework of international trade , but this transition implie serious prior organisation and a considerable cost to modify a country ' s road infrastructure (road signs , traffic lights , roundabouts , etc . ) .
