Definitions for "RANGE LIGHTS"
Two lights associated to form a range which often, but not necessarily, indicates a channel centerline. The front range light is the lower of the two, and nearer to the mariner using the range. The rear range light is higher and further from the mariner.
A pair of lighthouses which indicate a safe course when lined up one above the other. Sometimes one or both may be simple skeleton towers but older range lights can often be fine heritage structures. Example: Leards Range, PEI (front & rear).
Two lights or Day-Marks, located a distance apart, visible from one direction only. When one light is visible directly above the other, you are in the marked channel for safe passage.