Traffic at sea concentrates on efficient paths. A shipping lane is a regularly used route for commercial vessels, often following the shortest safe path between major ports or through constrained waters.

Some lanes are formal traffic separation schemes adopted by the IMO; others are customary routes shaped by weather, currents, and geography. Density of traffic in a lane increases collision risk and requires heightened watchkeeping. Coastal states and the IMO may regulate routing to protect the environment or to improve safety.

Passage planning takes account of recommended lanes and of the traffic likely to be encountered. Crossing a busy lane requires clear intentions and ample margin. Shipping lanes are the highways of the sea, and they carry most of the world’s seaborne trade.

• Regularly used route for commercial ships
• May be formal traffic schemes or customary paths
• High traffic density demands careful watchkeeping
• Central to global trade flow patterns