Short answer
Sweden follows the IALA system, Region A. Red lateral marks should be kept to port and green to starboard when you travel in the conventional direction of buoyage, which usually means heading towards land and harbour. Cardinal marks are yellow and black and show which side of a hazard has safe water. The topmark tells you the compass point.
Lateral marks (side marks)
| Mark | Colour | Topmark | Pass |
|---|---|---|---|
| Port-hand mark | Red | Red cylinder | Leave to port in the main direction |
| Starboard-hand mark | Green | Green cone, point up | Leave to starboard in the main direction |
The main direction is shown on the chart. If you are heading the other way, out of the harbour, the sides are reversed. The light on a lateral mark is the same colour as the mark.
Cardinal marks
The mark stands in the compass direction where you should pass. So you pass a north cardinal mark on its north side.
| Mark | Colours from top | Topmark (two cones) | Light (white) |
|---|---|---|---|
| North | Black over yellow | Both points up | Continuous quick |
| East | Black–yellow–black | Bases together | 3 flashes |
| South | Yellow over black | Both points down | 6 flashes + one long |
| West | Yellow–black–yellow | Points together | 9 flashes |
Memory aid: the tips of the cones point towards the black band.
Other brands
- Isolated danger mark: black with a red band and two black balls. It stands on or near a small hazard with navigable water all around, but keep your distance.
- Safe water mark: red and white vertical stripes and a red ball. There is navigable water all around the mark.
- Special mark: yellow with a yellow X, for example for cables, racing areas or speed limits. Check the chart for what it means.
- New danger: marked with duplicated marks until it appears on charts.
Lighthouses and light characteristics
At night you identify marks and lighthouses by the colour and rhythm of their light, not by their shape. The chart gives the light's character in abbreviations, for example Fl (flashing), Oc (occulting), Iso (equal periods of light and dark) and Q (quick flashing). The number after it gives the period in seconds.
- Sector lights show white in the safe channel and red or green on either side. If you see red or green, you are heading out of the channel – steer back towards the white.
- Leading marks are two marks or lights that should line up directly above each other. When they do, you are in the middle of the channel.
- Lit buoys often flash more faintly than lighthouses and are only visible at short range. Expect to see them late.
Practise by comparing the lights you see with the chart on the way home on a late-summer evening. It's the best way to learn, and it makes night sailing much safer.
In practice
- Always carry an up-to-date chart. Marks can be moved, and some are taken up over the winter.
- Learn the topmarks. Colours are hard to see against the light.
- Count the flashes at night and compare them with the light characteristic on the chart.
- Pass on the side of the compass point the cardinal mark indicates. Always check the depth and the extent of the hazard on the chart; the mark does not indicate a fixed safe distance.
See also the give-way rules.
Frequently asked questions
Which side should red marks be on?
To port when you are heading in the main direction of the fairway, usually towards land. Heading away from land, they are to starboard.
How do I tell a north mark from a south mark?
On the north cardinal mark both cones point up and the black is on top. On the south cardinal mark the cones point down and the black is at the bottom.
What does a yellow mark with a cross mean?
It's a special mark. What it marks is shown on the chart, for example a cable, an exercise area or a speed limit.
Sources
- Flytande sjömärken, Sjöfartsverket sjofartsverket.se
- Sjömärken, Sjöfartsverket sjofartsverket.se