Who invented the leap year calendar

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Travel A road trip in Burgundy reveals far more than fine wine. Travel My Hometown In L. Bluff City Life. About Us. Meet The Team. Editorial Board. Latest Newscasts. Investigate TV. Gray DC Bureau. Breakdown: Why we have a leap year. By Nick Gunter. Updated: Feb. Share on Facebook. Email This Link. These are the weirdest Leap Day myths But why do we even have leap years? Our calendar has days in a year, because that's pretty much how long it takes the Earth to orbit the Sun.

That discrepancy was spotted a while back. Leap year rules: Which years are leap years? What Is a Leap Year? Leap years are years where an extra, or intercalary, day is added to the end of the shortest month, February.

The intercalary day, February 29, is commonly referred to as leap day. Leap years have days instead of the usual days and occur almost every four years. Leap days keep our modern-day Gregorian calendar in alignment with Earth's revolutions around the Sun. It takes Earth approximately This is called a tropical year , and it starts on the March equinox.

However, the Gregorian calendar has only days in a year.