Leading line

With the Deckpeilung some harbor entrances are traditionally marks. It defines a straight line that extends from the shore towards the fairway.

To adjust the line - or the defined thereby short piece of waterways - to comply with two behind the other established markers, beacons or triangles must be kept under cover. The triangles sit on beacons and look ( at the distance ) with the tips of each other. This improves the accuracy of this simple bearing is much higher than say with a compass.

See also: Leading lights, Alignment (surveying ), cross-bearing, standing Bearing, Lateralsystem