A crossbuck is a traffic sign used to indicate a level railway crossing. It is composed of two slats of wood or metal of equal length, fastened together on a pole in a saltire formation (resembling the letter X). Crossbucks are often supplemented by electrical warnings of flashing lights, a bell, and/or a boom barrier that descends to block the road and prevent traffic from crossing the tracks.
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Crossbuck in the context of Level crossing
A level crossing is an intersection where a railway line crosses a road, path, or (in rare situations) airport runway, at the same level, as opposed to the railway line or the road etc. crossing over or under using an overpass or tunnel. The term also applies when a light rail line with separate right-of-way or reserved track crosses a road in the same fashion. Other names include railway level crossing, railway crossing (chiefly international), grade crossing or railroad crossing (chiefly American), road through railroad, criss-cross, train crossing, and RXR (abbreviated).
There are more than 100,000 level crossings in Europe and more than 200,000 in North America.
View the full Wikipedia page for Level crossing