Usuta, the unique footwear of the Incas, were a type of sandal worn by both men and women. The soles of usuta covered the bottom of the foot but ended at the balls of the foot. This left the toes exposed to help grip the ground of the mountainous terrain where the Incas lived. The soles of usuta were made from the untanned, or untreated, skin from the necks of sheep. Because the untanned usuta soles became soft in water, Incas removed their usuta in wet weather. Usuta were attached to the foot with thick, soft, tufted wool ties, which were dyed bright colors and sometimes patterned. These ties were secured around the instep, or top of the foot, and then wrapped around the ankle in decorative patterns.
Cobo, Bernabé. Inca Religion and Customs. Translated and edited by Roland Hamilton. Austin, TX: University of Texas Press, 1990.