Bolivia's indigenous group Aymara is observing the Skull Festival, called Day of the Ñatitas in their native language. People carry skulls, called ñatitas in native language, to the cemetery and pray, sing, and dance across the city in gratitude to those whose skulls they carry. National Geographic says the celebration combines Catholicism with pre-colonial Inca beliefs to give gratitude to the spirits occupying the ñatitas, whether buried or displayed throughout the year.