Maritime Symbols

Lines joining equal water depths — fathoms or metres depending on chart edition

Shallow water area — depth less than charted safety contour, shown in tinted area

Rock that covers and uncovers with tide — asterisk (*) symbol with depth

Rock permanently submerged — plus (+) symbol with depth value

Wreck with masts showing above water at lowest astronomical tide — skull symbol

Red can buoy — leave to port entering harbour in IALA Region A (Europe, Africa, Asia)

Green conical buoy — leave to starboard entering harbour in IALA Region A

Yellow/black pillar buoy, black top — pass to the north of danger

Black/yellow pillar buoy, yellow top — pass to the south of danger

Black/red pillar buoy, two black balls topmark — moored on or over isolated danger

Red and white vertical stripes, sphere topmark — safe navigable water on all sides

Yellow pillar or buoy, X topmark — special purpose feature (traffic, survey, aquaculture)

Continuous, unblinking light

Single flash at regular intervals — off period longer than on

Regular occultation — on period longer than off

Equal periods of light and darkness

Rapid flashing — approximately 60 flashes/minute

Flash of 2 seconds or more

Morse code letter characteristic — Mo(A) is •—

Circle with P — embarkation/disembarkation point for maritime pilots

Customs or port health authority offices

Coast radio station providing GMDSS DSC watch

Vessel Traffic Service radar coverage zone boundary