Lesson 6 of 13 · Module 2 — Finding your way

Cardinal, danger and safe-water marks

Yellow and black marks that say which side the danger is, plus isolated dangers, safe water, the yellow buoys round swimming areas and fish farms, and the wreck marking buoy.

Day Skipper18 minVideo · Notes · Interactive · Exercises

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0:00 / 4:39Chapter 1 of 10: Marks named after the compass

Transcript

Lateral marks show the sides of a channel, but many dangers lie out in open water, off a headland or in the middle of a bay. Cardinal marks guard them using the points of the compass. Imagine lines drawn out from the danger to the north-east, south-east, south-west and north-west. They split the sea around it into four quadrants: north, east, south and west. A cardinal mark sits in one of them, and you pass on its named side, so you pass north of a north cardinal.
Every cardinal mark is black and yellow, with two black cones on top, and the cones are the quickest way to read it. A north cardinal has both cones pointing up, and it is black above yellow. A south cardinal has both cones pointing down, and it is yellow above black. The cones always point to where the black is.
An east cardinal has its cones base to base, like an egg, and it is black with a yellow band. A west cardinal has its cones point to point, like a wine glass, and it is yellow with a black band. Again the cones point to the black: out to the top and bottom on the east mark, in to the middle on the west.
Every cardinal light is white, and it flashes quick or very quick. Now picture a clock face. East is at three o'clock and flashes in threes, south is at six and flashes six, and west is at nine and flashes nine. North, at twelve, flashes without a break. South adds one long flash after its six, so it cannot be mistaken for three or nine.
On the practice chart, The Teeth are rocks east of Gull Point, guarded by two cardinal marks. North Teeth buoy is a north cardinal, so you keep to the north of it. East Teeth buoy is an east cardinal, so you pass east of it, well clear of the rocks. Never cut between a cardinal mark and the danger it guards.
An isolated danger mark sits right on top of a small danger, such as a single rock, with safe water all round it. It is black with a broad red band, and its topmark is two black balls, one above the other. At night it flashes white in groups of two: two balls, two flashes. You can pass either side, but give it a wide berth, because the mark does not show how far the danger spreads. You will see them on rocks and shoals all over the Mediterranean.
A safe water mark has red and white vertical stripes, and a single red ball on top. It marks no danger at all, because there is safe water all round it. You find it at the seaward end of a channel, or as the first mark to look for when you arrive from sea. Its white light has an even, unhurried rhythm, such as one long flash every ten seconds.
Yellow marks are special marks, with a yellow cross on top if they have a topmark, and a yellow light if they are lit. They do not guide you in, they mark an area, and the chart or pilot book says what it is. In the Mediterranean you will meet two kinds above all. Lines of yellow buoys off a beach mark a swimming area, so anchor the yacht outside them and take the tender in slowly, by the marked lane if there is one. Yellow buoys and lights round a block of floating pens mark a fish farm, so give it room and never anchor or tie up to it. Cables, outfalls and racing marks can be yellow too, so always check the chart.
One mark is newer than the rest: the emergency wreck marking buoy. It has blue and yellow vertical stripes, and a yellow upright cross on top. At night it flashes blue and yellow, one after the other. It marks a new wreck that is not yet on the charts, so keep well clear.
These marks are the same in Region A and Region B, so they read the same in Greece and in the British Virgin Islands. By day, look at the topmark first, then the colours. By night, read the colour of the light, then count the flashes. Then ask two questions: what is it, and what does it tell me to do? Next, lights at night, and why charter companies ask you to arrive by daylight.

In this lesson you will learn

Name the four cardinal marks by topmark, colours and light, and pass each on its named side
Read cardinal lights with the clock face, including the south cardinal's long flash
Recognise isolated danger, safe water and emergency wreck marks, and say what each asks you to do
Recognise the yellow special marks round swimming areas and fish farms, and keep clear of them

Marks named after the compass

Lateral marks (Lesson 5) show the sides of a channel. Many dangers, though, lie out in open water: a reef off a headland, a shoal in the middle of a bay, a rock between two islands. Cardinal marks guard them using the points of the compass instead of port and starboard.

Imagine four lines drawn out from the danger on the true bearings north-east, south-east, south-west and north-west. They split the sea round it into four quadrants: north (315°–045°T), east (045°–135°T), south (135°–225°T) and west (225°–315°T). A cardinal mark is placed in one quadrant and named after it, and the safe water is on its named side.

The four quadrants round a danger. Each cardinal mark stands in its own quadrant, and you pass on its named side.

Pass north of a north cardinal, east of an east cardinal, south of a south cardinal and west of a west cardinal.

A danger may have one cardinal mark or several. Whichever you meet, never pass between it and the danger it guards.

The four cardinal marks

Every cardinal mark is black and yellow, with a topmark of two black cones. Read the cones first: they are the biggest clue, and they always point to where the black is on the mark.

North cardinal

Colours: Black above yellow

Topmark: Two black cones, both pointing up

Light: White, VQ or Q (continuous)

East cardinal

Colours: Black with one broad yellow band

Topmark: Two black cones, base to base

Light: White, VQ(3) 5s or Q(3) 10s

South cardinal

Colours: Yellow above black

Topmark: Two black cones, both pointing down

Light: White, VQ(6)+LFl 10s or Q(6)+LFl 15s

West cardinal

Colours: Yellow with one broad black band

Topmark: Two black cones, point to point

Light: White, VQ(9) 10s or Q(9) 15s

Mark	Cones	Colours	Memory aid
North cardinal	both pointing up	Black above yellow	Points up, as north is up.
East cardinal	base to base	Black with one broad yellow band	Base to base makes an egg shape: E for east (and egg).
South cardinal	both pointing down	Yellow above black	Points down, as south is down.
West cardinal	point to point	Yellow with one broad black band	Point to point makes a wine-glass shape: W for west (and wine glass).

InteractiveCardinal mark trainer

Name the mark and choose which side to pass. Try it by day, by night (count the flashes) or mixed.

Look at the topmark first, then the colours.

1. What is it?

2. Which side do you pass it?

Score: 0 of 0

Cardinal lights: think of a clock

Every cardinal light is white and flashes quick (Q, about once a second) or very quick (VQ, about twice a second). The number of flashes in a group follows a clock face:

East, at 3 o’clock: groups of three, Q(3)10s or VQ(3)5s.
South, at 6: groups of six and then one long flash, Q(6)+LFl15s or VQ(6)+LFl10s.
West, at 9: groups of nine, Q(9)15s or VQ(9)10s.
North, at 12: no groups, flashing without a break, Q or VQ.

The south light adds its long flash because quick flashes are hard to count from a moving boat, and six could easily be mistaken for three or nine.

InteractiveThe clock face

Watch the four lights side by side, quick or very quick.

North cardinal12 o’clockQ
White, quick flashing without a break
East cardinal3 o’clockQ(3)10s
White, quick flashing in groups of 3, repeated every 10 seconds
South cardinal6 o’clockQ(6)+LFl15s
White, quick flashing in groups of 6 followed by a long flash, repeated every 15 seconds
West cardinal9 o’clockQ(9)15s
White, quick flashing in groups of 9, repeated every 15 seconds

Each bar is one full period, lit parts in white; the marker shows where each light is now. Flash lengths are representative.

Cardinals on the practice chart

The practice chart has four cardinal marks. North Teeth and East Teeth buoys guard The Teeth, rocks awash east of Gull Point; South Brennan buoy guards Brennan Bank; and West Ledge buoy guards Head Ledge off Kerran Head.

Worked example

Which quadrant is East Teeth buoy in?

1Measure the bearing from the danger to the mark: from The Teeth to East Teeth buoy it is 101°T.
2That lies between 045° and 135°T: the east quadrant.
3So the buoy must be an east cardinal, and its light, Q(3)10s, agrees: three quick flashes, 3 o’clock.
4The safe water is to its east. Heading south past The Teeth, keep east of it, 0.53 miles or more from the rocks.

East quadrant, east cardinal: pass east of it.

InteractiveQuadrant explorer

Pick a cardinal mark, then place the yacht round it with the buttons or by tapping the chart. See which quadrant you are in and whether you are on the safe side.

North Teeth buoy (Q) is a north cardinal mark guarding The Teeth, rocks awash at chart datum. It stands 0.70 miles from them, bearing 000°T: inside the north quadrant, 315°–045°T.

Tap the chart to plot a positionZoom with + / −, drag to pan

Dashed lines: the quadrant boundaries, drawn out from the danger. Green: the side of the mark it tells you to pass. Hatched red: the danger.

Put the yacht half a mile from the buoy, or tap the chart:

✓ North of North Teeth buoy: the side it tells you to pass.

The yacht is 1.2 miles from The Teeth, bearing 000°T from them: in the north quadrant. As far as this mark is concerned you are in safe water. Keep an eye on the chart for anything else.

Isolated danger marks

An isolated danger mark sits right on top of a small danger, such as a single rock, a small shoal or a wreck, with navigable water all round it. One mark replaces a ring of cardinals.

	Isolated danger mark
Colours	Black with one or more broad red bands (bands run across)
Shape	Usually a pillar or spar buoy, or a beacon standing on the danger itself
Topmark	Two black spheres, one above the other
Light	White, flashing in groups of two: Fl(2)

“Navigable water all round” means you may pass on either side. It does not mean you may pass close: the mark shows where the danger is, not how far it spreads. You will see these beacons on rocks and shoals all over the Mediterranean. On the practice chart, Mew Rock beacon (Fl(2)5s) stands on a rock 2.7 miles south-west of Port Kerran that is covered for much of the tide.

Check your understanding: ahead you see a beacon with two black balls on top. Can you pass close to it?

Safe water marks

A safe water mark says there is navigable water all round it. It marks a place, not a danger: the seaward end of a channel, the middle of a channel, or a landfall mark to look for when arriving from sea. On the practice chart, Kerran Approach buoy (LFl10s) marks the start of the Port Kerran approach.

	Safe water mark
Colours	Red and white vertical stripes: the stripes run up and down
Shape	Spherical, pillar or spar
Topmark	Single red sphere (if it has one)
Light	White: isophase, occulting, one long flash every 10 seconds, or Morse A

Iso

Isophase

Equal light and dark

Occulting

More light than dark

LFl 10s

Long flash

One flash of 2 s or more, every 10 s

Mo(A)

Morse A

Short, then long

0 s5 s10 s

Ten seconds of each safe water rhythm on the same time scale. Only the long flash has a set period; the others are examples. Lesson 7 covers every light rhythm.

Special marks: swimming areas and fish farms

Special marks are yellow, with a yellow X on top if they have a topmark and a yellow light if they are lit. They do not show you the way; they mark an area or feature that the chart or pilot book explains. On a Mediterranean charter you will meet two above all.

Swimming areas

In summer, lines of small yellow buoys off a beach mark a swimming area. Keep the yacht outside the line, and take the tender in slowly, by the marked boat lane where there is one. Distances, speed limits and the way lanes are marked vary between countries and beaches, so follow local signs and the charter company’s briefing.

A typical swimming area: a line of yellow buoys off the beach, sometimes with a buoyed lane for boats. Not to scale.

Fish farms

Fish farms are common in sheltered bays in Greece, Turkey and Croatia: rows of round floating pens, with yellow special marks at the corners, often flashing yellow at night. The pens are held in place by mooring lines and anchors that spread well beyond them, so give the whole farm plenty of room, never anchor near it and never tie up to it.

A fish farm in plan: yellow special marks at the corners, with mooring lines spreading beyond the pens. Not to scale.

Yellow marks can also show an outfall pipe (the Outfall buoy on the practice chart, Fl Y 5s), a cable on the seabed, a water-ski area or a racing mark. When you see yellow, look it up.

The emergency wreck marking buoy

The newest mark in the system marks a new wreck that is not yet on the charts. It has blue and yellow vertical stripes, a yellow upright cross on top, and at night it flashes blue and yellow alternately. It stays until the wreck is charted and permanently marked. Keep well clear, and listen for navigational warnings on the radio.

Putting it together

Isolated danger mark

A small danger, navigable water all round

Safe water mark

Navigable water all round

Special mark

A special area: swimming, fish farm, cable

Emergency wreck marking buoy

A new wreck, not yet charted

The four marks after the cardinals, as you would see them from a boat.

All the marks in this lesson are the same in Region A and Region B: only lateral marks change between regions, so a cardinal reads the same in Greece and in the British Virgin Islands.

InteractiveThe practice chart's other marks

Zoom in on Mew Rock beacon, Kerran Approach buoy and the Outfall buoy, see each light at night and what to do.

Mew Rock beacon: 49°44.0'N 004°15.0'W

white, group flashing, 2 flashes every 5 seconds0.0 s of 5 s

Mew Rock beacon

Isolated danger mark · Fl(2)5s

• Rock dries 1.2 m: often covered
• Two white flashes every 5 s

An isolated danger mark: a beacon standing on Mew Rock, 2.7 miles south-west of Port Kerran. The rock is a small danger with navigable water all round it.

What to do: Pass on either side, but give it a wide berth: the beacon shows where the rock is, not how far it spreads underwater.

InteractiveWhat is it, and what do I do?

Every mark in this lesson, by day or at night: name it, then choose what to do.

Every mark in this lesson

By day: topmark first, then the colours.

1. What is it?

For any mark, ask two questions: what is it, and what does it tell me to do? By day read the topmark, then the colours; by night read the colour of the light, then count.

Next: lights at night, and why charter companies ask you to arrive by daylight.

Key terms

Cardinal mark: A black and yellow mark placed in one quadrant of a danger, with the safe water on its named side.
Quadrant: One quarter of the sea round a danger, bounded by the true bearings NE, SE, SW and NW from it.
Topmark: The shape on top of a mark: two black cones on a cardinal, which point to where the black is.
Q, VQ: Quick flashing (about once a second) and very quick flashing (about twice a second): the rhythms of cardinal lights.
Isolated danger mark: Black with a red band and two black balls; on a small danger with navigable water all round. Light white Fl(2).
Safe water mark: Red and white vertical stripes and a red ball; navigable water all round, often a landfall or channel start.
Special mark: Yellow, with a yellow X if it has a topmark: an area or feature such as a swimming area, fish farm, cable or outfall.
Emergency wreck marking buoy: Blue and yellow vertical stripes, yellow upright cross, alternating blue and yellow light: a new, uncharted wreck.

Exercises

Check your understanding. You get a second try at each question, then the worked answer. Score 70% or more to complete the lesson; your progress is saved in this browser.

You see this buoy off a headland. What is it?

A buoy is painted black above yellow, with a topmark of two black cones, both pointing up. Which side should you pass it?

Which of these lights would you expect on an east cardinal mark?

You see this white light at night. Watch it and count the flashes in a group (Restart begins a fresh group). What is it, and which side do you pass?

A cardinal mark is charted on a true bearing of 280° from the rock it guards. Which mark is it, and where is the safe water?

To check which quadrant of The Teeth East Teeth buoy is in, measure the true bearing of the buoy FROM The Teeth: put A on The Teeth and B on the buoy.

Distance A→B: 0.45 MBearing A→B: 090°TDrag A and B, or Tab to them and use the arrow keysZoom with + / −, drag to pan

South Brennan buoy (Q(6)+LFl15s) guards Brennan Bank on the practice chart. Tap a spot about half a mile from the buoy, on the side where the safe water is.

Sailing between islands in Croatia, you see a beacon on a small rock: black with a broad red band and two black balls on top. What do you do?

Ahead is a buoy with red and white vertical stripes and a single red ball on top. What does it tell you?

Arriving in a bay on Mallorca, you see a line of small yellow buoys strung across the bay, parallel to the beach. What are they most likely to mark, and what do you do?

Late in the evening in a Greek bay, you see several yellow lights flashing round a dark patch of water ahead. What is it most likely to be?

A buoy with blue and yellow vertical stripes and a yellow upright cross on top has appeared since your chart was printed. What does it mark?

0 of 12 answered · 0 correct

Marks practice

Six fresh questions each time: name a cardinal by day or night, choose the side to pass, a quadrant bearing, the practice chart's cardinals, and what to do at an isolated danger, safe water, special or wreck mark.