Calendopaedia - The Encyclopaedia of Calendars

Welcome to THE source of data on calendars.

I recommend that you start by looking at the Comparison of Calendars.

Alternatively you could choose from one of these pull-down meus then click 'Go'.


Since the dawn of civilisation man has kept track of time by use of the sun, the moon, and the stars. Man noticed that time could be broken up into units of the day (the time taken for the earth to rotate once on its axis), the month (the time taken for the moon to orbit the earth) and the year (the time taken for the earth to orbit the sun).

This information was needed so as to know when to plant crops and when to hold religious ceremonies. The problems were that a month is not made up of an integral number of days, a year is not made of an integral number of months and neither is a year made up of an integral number of days. This caused man to use his ingenuity to overcome these problems and produce a calendar which enabled him to keep track of time.

The ways in which these problems were tackled down the centuries and across the world is the subject of this Web site. It is recommended that you start by looking at the Comparison of Calendars.

This page was produced by Michael Astbury. Thanks to all the reference sources which I have quoted (too many to list them all) and to all the friends who have contributed to these pages in so many ways.

If you have any comments, corrections or suggestions then please email me.

This site does not use frames so you the reader are in control of your own screen. This site is low on graphics so that its pages load quickly. This site does not use white text so you will have no problems printing any of the pages.

Are you interested in mazes? If so visit my other site - Mike's Mazes.

This site was updated on Thursday 19th August 2010 AD (Gregorian). Find out what's new.

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