Trail blazing, or trailblazing (way marking in United Kingdom and Ireland), also used in North America, Australia and New Zealand, is the practice of marking paths in outdoor recreational areas with blazes, markings that follow each other at certain — though not necessarily exactly defined — distances and mark the direction of the trail. Originally a tree would be blazed by hatchet chops (still the dictionary definition) but today other methods have become more common, with environmental and aesthetic concerns sometimes playing a part in the choice of blazing method. Other navigational aids, such as cairns, are used where blazes are unsuitable.