In the next section we will touch on some essential points to consider on a chart. Entering a port you will see green buoys on the right of the channel and red buoys on the left of the channel. Looking at the chart it will tell you the depth of the water inside and either side of the channel. Channels may be for big ships or for everyone. In the port of Piraeus for example, the channel will be for big ships, where smaller boats like yours can sail safely outside of the channel without getting mixed up with something 1000 times your size. In a tiny sailing port the channel will be for everyone, and may indicate that you will run aground outside it. You may hit rocks or coral as well as sand so could damage the boat – use your intelligence!

Entering and leaving port you should pass on the right hand side of the channel – by the green buoys on the way in and by the red buoys on the way out.


A chart tells you so much more than a road map. Where roads are generally safe you stick to them and you will not come to harm. Except navigating down channels you can go wherever you choose as long as it is safe – and the chart will tell you where it is and isn’t!

If you have no idea about using a chart for navigation, do a course before you go. Understanding what is going on on a chart is as essential as knowing how to put on a lifejacket, and not understanding is as silly as jumping over the side and imagining you can swim back to the UK.

Here are some basics to jog your mind.

Blue / yellow

Yellow areas on the chart is the land. Blue is the sea.

The darker blue the area the shallower the water. Generally there will be lines around the different contours of depth. There are rocks in funny places – don’t ignore them. In the last Volvo Ocean Race a navigator didn’t zoom his digital chart in enough and presuming they were in open ocean they hit a shoal off an island in the Indian Ocean he hadn’t spotted at over 20mph, and ripped the bottom out of the boat. Needless to say he isn’t a navigator any more…

The depths will be numbers on the chart and are measured in metres.


Occasionally there will be a shipwreck that is partially exposed. That’s a little safer than where one isn’t and is under water. There will be a dotted line around the wreck and a depth to the top of that wreck. That will be similar to a rock or shoal where the measured depth will be circled.


On the land and on some exposed rocks there will be a lighthouse. This is denoted on the chart with a dot, a red cone and some shorthand that will dictate what you see:

For example: F(3)W

F means flashing

(3) will mean it is flashing three times

means that the light is white.

Every lighthouse in a locality will have different day markings and night flashing patterns. Use your Chart Number 1 to decipher what is what.


Broadly, a solid red buoy should be left to port entering port. The green buoy should be left to starboard entering port. On the chart the red channel marker will be a square with a circle in the bottom of the line. The green buoy will be a cone with a circle along the line on the bottom.


Danger marks are there to prevent people from hitting something on the bottom. This might be a shoal, rocks, a sand bar or a wreck.

Cardinal Marks are painted white, black and yellow. On the chart as well as the buoy you will see shapes:

Pass to the North: Two black cones pointing upward

Pass to the South: Two black cones pointing downward

Pass to the East: Top cone upwards, bottom downwards (you can imagine you can draw an E in them)

Pass to the West: Both cones pointing to the middle. (You can imagine a W in them)


This is a discipline you should only do with some experience – at least 2-3 times under someone else’s supervision. If not, try to be in port before nightfall as sailing in the dark is 100 times more stressful than during the day. It is a discipline in its own right and you really need to know what you are doing.

Make sure you have done a navigation course – and passed the exam before you venture out at night.


All vessels have to show prominent navigation lights. For sailors the most annoying things afloat are ferries and cruise ships as they have their lounge and cabin lights on – they are often so bright you cannot see their navigation lights and you must guess their direction of travel.

Excepting these if you see red lights on a vessel you are looking at its port side. If you see green lights you are looking at its starboard side.

If you see red and green with a white light above, it is a motor vessel coming toward you. If you only see a white light it is going away from you – the odds are you will see a port or starboard light as you pass by.

If you only see green or red / green and red but no white masthead light it is a sailing vessel.

If you are coming into an anchorage or port and see a white light on the mast, it is a vessel at anchor.

Channel markers

Channel marking buoys in larger ports will have lights on them. If it is a green light, leave it to starboard and red to port.


If you see a flashing yellow light that is an isolated danger mark – it could be a new wreck. Avoid it.

Leave to the North: White light very quick flashing

Leave to the South: White light 6 quick flashes and a long flash every 10 or normal flashes every 15 seconds.

Leave to the East: White light 3 quick flashes every 5 seconds or 3 normal flashes every 10 seconds

Leave to the West: White light 9 quick flashes every 10 seconds or normal flashes every 15.


As discussed above, lighthouses will have a specific flashing pattern that will identify it from all the others in the locality.