Hoodoos are found mainly in the desert in dry, hot areas. In common usage, the difference between hoodoos and pinnacles (or spires) is that hoodoos have a variable thickness often described as having a "totem pole-shaped body". A spire, on the other hand, has a smoother profile or uniform thickness that tapers from the ground upward. An example of a single spire, as an earth pyramid, is found at Aultderg Burn, near Fochabers, Scotland.
Hoodoos range in size from the height of an average human to heights exceeding a 10-story building. Hoodoo shapes are affected by the erosional patterns of alternating hard and softer rock layers. Minerals deposited within different rock types cause hoodoos to have different colors throughout their height.
Hoodoos are commonly found in the High Plateaus region of the Colorado Plateau and in the Badlands regions of the Northern Great Plains (both in North America). While hoodoos are scattered throughout these areas, nowhere in the world are they as abundant as in the northern section of Bryce Canyon National Park, located in the U.S. state of Utah (see geology of the Bryce Canyon area). They are also very prominent a few hundred miles away at Goblin Valley State Park on the eastern side of the San Rafael Swell.
Hoodoos are a tourist attraction in the Cappadocia region of Turkey, where houses have been carved from these formations. These rock formations were depicted on the reverse of the Turkish 50 new lira banknote of 2005–2009.
In French, they are called demoiselles coiffées ("ladies with hairdos") or cheminées de fées ("fairy chimneys") and a number of them are found in the Alpes-de-Haute-Provence; one of the best-known examples is the formation called Demoiselles Coiffées de Pontis.