A burrow is a hole or tunnel excavated into the ground by an animal to construct a space suitable for habitation or temporary refuge, or as a byproduct of locomotion. Burrows provide a form of shelter and protection from harsh conditions or predators. Some mammals that are known to burrow include rabbits, groundhogs, foxes, and weasels. Burrows may be found facing the direction of sunlight or away from the direction of cold wind, which could help with heat retention and insulation, providing protection from temperatures and conditions outside. Burrows may also be used by certain species as protection from harsh conditions, or from predators.