What do green colors, green lights, and odd numbers indicate?

Green colors, green lights, and odd numbers are maritime markers that indicate the edge of the channel on your port (left) side as you enter from the open sea or a larger body of water. This is an established convention in navigation known as the IALA (International Association of Lighthouse Authorities) buoyage system, particularly in regions following the "International" buoyage system or the "Region A" system.

In this system, the green markers are arranged so that boaters can safely navigate by keeping these markers on their left-hand side when entering a channel from seaward. This helps in maintaining a safe passage through the navigable waters and indicates to the boater that they are approaching the left edge of the navigable channel.

Understanding these cues is crucial for safe navigation, particularly in busy or unfamiliar waterways where proper channeling can prevent groundings or collisions.