About once every four years, we have a ‘leap year’ and February gains an extra day. Apart from helping to keep our calendars in sync, February 29th has also prompted some interesting traditions throughout time.
Since 2024 is a leap year, we’ve taken a closer look at how they came to be, and pulled together eight fun facts.
Why do we have leap years?
Almost everyone is familiar with the concept of a leap year, but the reasoning behind why we have them is a little more complicated.
We all know that a calendar year is typically 365 days long and is loosely defined by the number of days it takes the Earth to orbit the sun. But, what’s lesser known is that 365 is actually a rounded number. In reality, it takes 365.242190 days for Earth to orbit the sun – or, 365 days, 5 hours, 48 minutes, and 56 seconds!
While this may not seem significant, this extra time needs to be accounted for. Otherwise, the seasons would gradually fall out of sync. In fact, over a period of 700 years or so, our summers – which typically arrive in June in the northern hemisphere – would begin in December instead.
The concept of having an extra day every four years to make up for this excess time was first introduced by Julius Caesar in 45 B.C. with the creation of the Julian calendar. However, it turned out that once every four years was too often, meaning that, by 1582 AD, this slight discrepancy had added up to 10 days.
It was for this reason that Pope Gregory XIII created the Gregorian calendar in 1582 and coined the term ‘leap year’ – establishing 29th February as its official date. Now, leap years occur in every year that’s divisible by four – but only in century years that are evenly divided by 400. For example, 800, 1200, and 2000 were leap years, but 1700 and 1900 weren’t.
8 fun facts about leap years
Now that we know more about the history and science behind why we have leap years, what are some of the traditions that this extra day has led to over the years?
1. During leap years, January, April, and July all start on the same day
Every leap year, these months all start on the same day. In 2024 they’ll all start on a Monday. And, in 2020, they all began on a Wednesday, as you can see by looking at this calendar.
2. There’s an official leap year cocktail
Unsurprisingly…it’s called the Leap Year Cocktail! Crafted on 29th February, 1928, the Leap Year cocktail is a well-rounded martini alternative.
Gin is paired with sweet vermouth and the brandy-based orange sweetness of Grand Marnier. The result is so deliciously refreshing that you might argue it deserves to be enjoyed more than once every four years!
Check out this Leap Day Cocktail recipe from Serious Eats to have a go at making your own.
3. Leap seconds won’t exist from 2035
Every now and then, we also add a one-second adjustment (known as a ‘leap second’) to our clocks to synchronise them with the Earth’s rotation.
Leap seconds were first introduced in 1967, but a recent vote by the International Bureau of Weights and Measures will lead to their suspension in 2035, as it’s believed they’re no longer proving useful.
With no more leap seconds to be added until at least 2135, this decision is founded on the hopes that people in the next century will come up with a better system of keeping our calendars aligned!
4. People born on 29th February are called ‘leaplings’ or ‘leapers’
People born on 29th February will prepare to celebrate their actual birthday in 2024 for the first time since 2020. During non leap years, so-called ‘leaplings’ or ‘leapers’ must choose to celebrate their birthday on either 28th February or 1st March.
While there are both ups and downs to having a leap day birthday, it’s certainly unique. In fact, according to research, there’s a one in 1,461 chance of being a ‘leapling’.
Famous ‘leaplings’ include Pope Paul III (1468-1549), English poet John Byrom (1692-1763), Italian composer Gioacchino Rossini (1792-1868), and British actor Joss Ackland (1928-2023).
5. Tradition says it’s okay for women to propose to men on 29th February
There’s a tradition that women propose to men on 29th February, rather than the other way around. There are a few contending theories as to where this idea came from.
The first goes that an Irish nun, Brigid of Kildare, pleaded with Irish patron saint St Patrick for women to have a chance to propose to shy suitors, to which he obliged on February 29th.
Another contender is that Queen Margaret of Scotland passed a law in 1288 that women could propose on 29th February. And, if a man refused, he had to pay a fine of new gloves, a gown, or a kiss.
However, a more likely reason stems back to 1582, when Pope Gregory XIII created the Gregorian calendar. The idea of adding an extra day every four years seemed so ridiculous to many that a British play joked it would be a day when women should trade their dresses for ‘breeches’ and act like men.
The play was a satire, but it may have inspired some early feminists as by the 1700s, women were using leap days to propose to men. The tradition peaked in the early 1900s, but even today some UK retailers offer discounts to women planning to pop the question.
6. Some ancient calendars had entire leap months
Some ancient calendars, including Hebrew, Buddhist, and Chinese calendars, were lunisolar – meaning their dates indicate the position of the Moon, as well as that of Earth, in relation to the Sun.
However, because there’s a gap of around 11 days between the Earth’s orbit and a lunar cycle, these calendars require the addition of extra months (known as intercalary months) every so often to keep them on track.
For example, it’s not entirely clear how the early Romans kept track of their years, but it’s believed that their calendar consisted of 10 months plus an undefined stretch of time throughout winter. Eventually, this winter period was replaced by the months of January and February – as well as an intercalary month, known as Mercedonius, to account for the remaining amount of time.
It was for this reason that the Roman year and the solar year were so out of sync by Julius Caesar’s time.
7. Only Swedes and Hobbits celebrate 30th February
An even rarer date than 29th February? Enter 30th February. In 1712, Sweden and Finland (considered part of Sweden at the time) added a one-off extra Leap Day to February to help get their outdated Julian calendar up to speed with the new Gregorian calendar.
However, only true Lord of the Rings fans will know that there’s only one race of people who celebrate 30th February every year: Hobbits. Hobbits observe twelve 30-day months each year, including Solmath (translated in the text to February).
8. A little town in Texas is the self-proclaimed ‘Leap Year Capital of the World’
The town of Anthony in Texas, USA, is the self-proclaimed ‘Leap Year Capital of the World’.
In 1988, local resident Mary Ann Brown and her neighbour Birdie Lewis – born on 29th February – approached the Chamber of Commerce with the idea of hosting a celebration for everyone born on a leap day. The celebration would give the town local recognition and help to raise funds for the community.
Now, each leap day, Anthony holds a four-day festival and birthday celebration for all leap year babies. People travel from across America and abroad to take part in the parades, birthday dinners, and hot air balloon rides.
The history of leap years is a unique one, and it’s fascinating to think that, after all this time we still haven’t figured out a way to consistently keep our calendars in sync.
However you decide to spend the extra day in 2024, we hope you’ve enjoyed these eight fun facts about leap years.
Which of the facts about leap years has surprised you the most? Do you have any other facts you’d like to share? We’d love to hear from you in the comments below!