Cardinal Marks

Cardinal Marks are used in conjunction with the compass to indicate the direction from the mark in which the deepest navigable water lies, to draw attention to a bend, junction or fork in a channel, or to mark the end of a shoal.  

Mariners will be safe if they pass North of a North mark, South of a South mark, East of an East mark and West of a West mark. Cardinal Marks are also used for permanent wreck marking whereby North, East, South and West Cardinal buoys are placed around the wreck. In the case of a new wreck, any one of the Cardinal buoys may be duplicated and fixed with a Radar Beacon (RACON). 

At night, the light character of a Cardinal Mark will be programmed to flash in accordance with positions on a clock face whereby a North Cardinal will flash 12 times, an East Cardinal 3 times, a South Cardinal 6 times and a West Cardinal 9 times.

The buoy illustration shows Class Two configurations of buoys. These are approximately 3 metres in diameter and weigh approximately 6 tonnes excluding moorings. Buoys are needed to be recognised both in daylight and at night and use 'Top Marks' to assist in identification. A Top Mark on a Cardinal Buoy is triangular and coloured black. Top Marks and buoy colours themselves are arranged in order to represent the points on a compass.

Above (Left to Right): North, East, South and West Cardinal Class Two Solar Buoys