BOAT-COMPARATOR Guide
Reading Maritime Buoys: The Buoyage System Every Boat Renter Should Know
Red to port, green to starboard, cardinal marks, special marks: the basics of the IALA buoyage system, useful even on a license-free boat.
A marked channel isn't decoration — every buoy carries a specific piece of information about depth, a hazard, or a restricted zone. Here's enough to read a chart with confidence.
Lateral marks: red and green
In Europe (IALA Region A), red cylindrical buoys mark the port side of a channel when entering a harbour or heading upriver, and green conical buoys mark the starboard side. The simplest way to remember it: entering harbour, keep red to your left and green to your right.
Cardinal marks: where the danger lies
These black-and-yellow buoys flag a localised hazard by showing which side to pass it on: a north cardinal is passed to its north, a south cardinal to its south, and likewise for east and west. Their black-and-yellow banding and the number of points on their top marks let you identify them even from a distance.
Special marks and isolated danger marks
A yellow buoy flags a specific area — an underwater cable, a swimming zone, a channel limit reserved for a particular use. A black buoy with red bands, topped with two black spheres, marks an isolated danger — a rock or a wreck — to be given a wide berth from any direction.
Why it matters even on a license-free boat
On a license-free rental, no formal training is required, but the channels leading into harbours are marked the same way regardless: recognising a red or green buoy heads off the most common grounding, the one that happens on the way in or out of a harbour from simple unfamiliarity with the marks.
Going further
This pairs naturally with our VHF and safety at sea guide and our essential knots guide — the core of a good departure briefing fits into these few simple reference points.
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