Marks the port (left) side of the channel entering from seaward. Red, can-shaped, carries even numbers. Keep it on your port side when heading in.

Marks the starboard (right) side of the channel entering from seaward. Green, conical, carries odd numbers. Keep it on your starboard side when heading in.

At a channel bifurcation; the preferred route is to port. Red with a green horizontal band, can topmark. Leave to port.

At a channel bifurcation; the preferred route is to starboard. Green with a red horizontal band, conical topmark. Leave to starboard.

Navigable water lies to the NORTH of this mark. Black top, yellow bottom; two cones pointing up. White quick-flashing light (continuous).

Navigable water lies to the EAST of this mark. Black–yellow–black; two cones pointing apart. White light: Q(3) or VQ(3) every 5s.

Navigable water lies to the SOUTH of this mark. Yellow top, black bottom; two cones pointing down. White light: Q(6)+long flash, or VQ(6)+LFl.

Navigable water lies to the WEST of this mark. Yellow–black–yellow; two cones pointing together. White light: Q(9) or VQ(9).

Marks an isolated danger with navigable water all around it (e.g. a lone rock or wreck). Black with one or more red horizontal bands; two black balls vertically. White light Fl(2).

Indicates navigable water all around — safe to pass on either side. Red and white vertical stripes; single red ball topmark. White light: Iso, LFl, or Fl.

Indicates a special area or feature — anchorage, recreation zone, military exercise, cables/pipelines, or data-collection. Yellow with a yellow X (St Andrew’s cross) topmark. Yellow light (any rhythm not white/green/red).