Why is Portside Red and Starboard Green?


Why is Portside Red and Starboard Green? For this, you have to go back to the history of maritime antiquity and the reasons why they are called Portside and starboard in the first Place.

The reason Portside is Red and Starboard Green is down to the steering and mechanism of the older oar-driven boats.

Steering mechanism denoting Portside and Starboard

Early boats used oars for steering rather than a centralized rudder. The steering oar was typically on the right-hand side of the vessel. This placement allowed the helmsman a better view of the right side but obstructed their view of the left, making the left side the more hazardous or “danger” side.

Colour association of Portside and Starboard

To denote this dangerous side, the left side was often marked with the colour red, which has universally been understood as a warning or danger colour.

Passing of boats to protect the steering oars.

When boats approached each other, they would pass with their left sides facing each other. Despite the reduced visibility, this practice protected the steering oar—the most critical steering component—from potential collisions.

Similarly, when docking or tying up, boats would secure their left side (port side) to protect the steering oar, which was on the right side. This practice ensured that the most crucial steering component was less likely to be damaged in port.

For an easy way to remember this check out our post on remembering Portside and Starboard.

Ship terminology diagram What is the front of a ship called? how to remember Stern
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  • Donna Vallance

    Donna loves cruising with her husband and two teenage boys. Having cruised with the children from a young age she feels it is the perfect way to experience the world safely. Her boys are social butterfly’s and love meeting other children their own age whilst onboard some of the most extraordinary floating ships. She also writes over at Like Love Do, a travel memoir of her trips, from London to far off beaches. She has an eye for the unusual and like to go off of the beaten track just to find the perfect photo. With a passion for photography and exploring cruising has become the perfect holiday choice.

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