Dec. 17, 1790: Accurate Calendar Requires Sacrifice, You Dig?

Workers doing repairs in Mexico City unearth a massive stone bearing ancient symbols. It turns out to be a representation of the Aztec calendar and will eventually become a national treasure.

Source: http://www.wired.com/thisdayintech/2012/12/dec-17-1790-accurate-calendar-requires-sacrifice-you-dig/

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