Muisca calendar

The Muisca calendar was a lunisolar calendar used by the Muisca. The calendar was composed of a complex combination of months and three types of years were used; rural years (according to Pedro Simón, Chibcha: chocan), holy years (Duquesne, Spanish: acrótomo), and common years (Duquesne, Chibcha: zocam). Each month consisted of thirty days and the common year of twenty months, as twenty was the 'perfect' number of the Muisca, representing the total of extremeties; fingers and toes. The rural year usually contained twelve months, but one leap month was added. This month (Spanish: mes sordo; "deaf month") represented a month of rest. The holy year completed the full cycle with 37 months.

The Muisca were one of the four advanced civilizations of the Americas before the arrival of the Europeans inhabiting the central highlands of the Colombian Andes (Altiplano Cundiboyacense) and as the other three (Aztec, Mayas and Incas) they had their own calendar, arranged by Bochica. Important Muisca scholars who have brought the knowledge of the Muisca calendar and their counting system to Europe were Spanish conquistador Gonzalo Jiménez de Quesada who encountered Muisca territory in 1537, Bernardo de Lugo (1619),Pedro Simón in the 17th century and Alexander von Humboldt and José Domingo Duquesne published their findings in the late 18th and early 19th century. At the end of the 19th century, Vicente Restrepo wrote a critical review of the work of Duquesne.

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