Lateral marks show the sides of a channel relative to the conventional direction of buoyage (usually from seaward towards the harbour). This is the only family that differs between the regions: in Region A the port hand is red and the starboard hand green; in Region B it is the other way round.
Region A (Europe, Australia, New Zealand, Africa, the Gulf, most of Asia): „is there any red port left?”, red to port entering from seaward. Region B (the Americas, Japan, Korea, the Philippines): the opposite, „red right returning”.
Region A, port hand
Colour
red
Buoy shape
can (cylindrical)
Topmark
a single cylinder (can)
Light
any (other than Fl(2+1))Any rhythm, as long as it is not Fl(2+1). Below: a sample single flash.
What it means
Entering the channel from seaward, leave this mark on your port side.
Region A, starboard hand
Colour
green
Buoy shape
conical (nun)
Topmark
a single cone, point up
Light
any (other than Fl(2+1))Any rhythm, as long as it is not Fl(2+1). Below: a sample single flash.
What it means
Entering the channel from seaward, leave this mark on your starboard side.
Region B, port hand
Colour
green
Buoy shape
can (cylindrical)
Topmark
a single cylinder (can)
Light
any (other than Fl(2+1))Any rhythm, as long as it is not Fl(2+1). Below: a sample single flash.
What it means
Entering the channel from seaward, leave this mark on your port side.
Region B, starboard hand
Colour
red
Buoy shape
conical (nun)
Topmark
a single cone, point up
Light
any (other than Fl(2+1))Any rhythm, as long as it is not Fl(2+1). Below: a sample single flash.
What it means
Entering the channel from seaward, leave this mark on your starboard side.
Facts per the IALA Maritime Buoyage System (MBS ed. 2.0). The drawings are our own vectors. The light rhythm and colour in the drawing are illustrative: check the real characteristics of a specific buoy on the chart and in the list of lights.