Oruro, Bolivia, February 1, 2008—Miners carry a llama's heart at the Itos silver and base-metal mine during the Carnival of Oruro celebration. Each year the workers sacrifice llamas during an underground ritual in honor of Mother Earth and the Aymara Indian god Tio, ruler of the underworld.

Declared as one of the ''Masterpieces of the Oral and Intangible Heritage of Humanity'' by UNESCO in 2001, the Oruro festival is the biggest cultural event in the country.

Though it traces its roots to ancient Andean customs, the Carnival of Oruro has since transformed largely into a Christian ritual.

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