A plantar wart is a skin lesion on the sole of the foot that is caused by a virus. A plantar wart is often mistaken for a corn or callous because it has a similar appearance, usually a circular area of thick skin that creates discomfort with weight-bearing. The classic sign of a wart is the appearance of tiny “black dots” within the lesion. Warts can occur on any area of skin, including around toenails, but they tend to occur on the sole of the foot because this area is the most susceptible to micro-trauma which creates an entry point for the wart virus. Warts seem to be more prevalent in children and young adults; one theory is that adults have had more time to develop immunity to the wart virus.