Left- and right-hand traffic

Left-hand traffic (LHT) and right-hand traffic (RHT) are the practices, in bidirectional traffic, of keeping to the left side or to the right side of the road, respectively. They are fundamental to traffic flow, and are sometimes referred to as the rule of the road.

In LHT traffic keeps left, and cars usually have the steering wheel on the right (RHD – right hand drive), putting the driver on the side closer to the centre of the road. Roundabouts circulate clockwise. RHT is the opposite of this: traffic keeps right, the driver usually sits on the left side of the car (LHD), and roundabouts circulate anticlockwise.

In most countries rail traffic follows the handedness of the roads, though this is not always the case. Boat traffic on rivers is effectively RHT. Boats are traditionally piloted from the starboard side to facilitate priority to the right.

Worldwide Distribution by Country

Country	Road traffic	Date of switch	Notes, exceptions
Creeperopolis	RHT		Some roads in Creeperopolis are only one lane-wide, such as the Yungas Road, and require cooperation and maneuvers from both directions of traffic to drive smoothly and safely.
Gjorka	RHT
Greater Sacramento	RHT
Groffenord	LHT
Karimun	LHT
Lyoa	RHT
Malgax	RHT
New Gandor	RHT
Paleocacher	RHT
Quebecshire	RHT
Rakeo	RHT
Reia	LHT
Salisford	RHT
Sequoyah	NO DATA
Terranihil	RHT
Tirol	LHT	1924	In some rural areas with distinct road systems RHT is used.