Greenwich Time: Home of World Time (GMT) since 1884
Complete guide to times in every time zone in the world.
GreenwichMeanTime.info Details

Indian Moons
A list of many American Indian tribe's names for months, days, and other calendar related information.
www.americanindian.net Details

Julian Day Numbers
An explanation of the Julian day number system used by astronomers and calendricists.
www.hermetic.ch Details

Leap Seconds
Civil time is occasionally adjusted by one second increments called leap seconds. A detailed explanation of what a second actually is, and why leap seconds are necessary.
tycho.usno.navy.mil Details

LunarCal - A Perpetual Chinese Lunar Calendar
LunarCal is a 160-year perpetual Chinese Lunar Calendar for 1900 to 2060. Chinese festivals are listed and the moon phase is displayed.
www.geocities.com Details

Lunisolar Calendar
Lunar calendar with lunations, from new moon to new moon, instead of months. Moon phase on each day. Chinese, Jewish, and Islamic months. Eclipses, meteors, planets, star charts. Christian, Pagan, Islamic, Hindu, and Jewish holidays.
www.pburch.net Details

Maya Calendar 2000
The calendar was the center of Maya life and their greatest cultural achievement. To carry out their astronomical calculations they developed a sophisticated mathematical system. The Maya Calendar website is developing with the intent of providing a complete view of Maya culture.
mayacalendar.com Details

Millennium Mistake
Explains the difference between millenium and year 2000 as the absence of a year zero.
www.millenniummistake.net Details

Rosetta Calendar
An online handy tool for converting to and from the Gregorian, Julian and Jewish calendars.
rosettacalendar.com Details