Trailblazing

Trail blazing is to make a mark on a tree by slashing the bark to indicate the direction of a trail through forested wilderness.Way marking with signs, or other markers, is used in non-forested landscapes, and in outdoor recreational areas. In both cases the blazes, or markers, follow each other at unspecified intervals, determined by the judgement of the person blazing the trail. They are placed so that travelers will not lose the trail, and will understand trail intersections.

There are several ways of marking trails: paint, carvings, affixed markers, posts, flagging, cairns, and crosses, with paint being the most widely used.

A painted marking of a consistent shape or shapes (often rectangular), dimension and colour or combination of colours is used along the trail route. The system by which blazes are used to signify turns and endpoints in trails (see below) strongly favors the use of paint blazes.

European countries usually use systems of painted bars or shapes in more than one colour. The Central European Hiking Markers System pictured above is one. This system use three bars - usually one color in between two white bars, with different meanings attached to different colours - in a 10 cm x 10 cm square. Red is often used to mark difficult or summit trails. Arrows of similar design signal a change of direction. Originally created in the Czech Republic, this system to Slovakia, Poland, Croatia, Bosnia, Ukraine, Bulgaria, Georgia, Brazil and other countries. French, Italian, Austrian and Swiss trails use a similar system of white and coloured stripes.

In the United States and Canada, it is a single colour, often white, red, blue or yellow. Trails in South Africa are often marked by yellow footprints painted on trees and rocks.

Blazes may also be painted on obvious rock surfaces or on posts set into the ground (or on utility poles, fences, or other handy surfaces) where the trail follows a road or goes through fields and meadows.

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Wikipedia