The winter solstice marks the longest night of the year. This event has influenced holidays and traditions around the world, and you can find plenty to see as you travel during this part of the year. Here are four festive facts we bet you never knew about the winter solstice.

Stonehenge Is Designed to Align With the Sunset on the Winter Solstice

Sunlight has been important to cultures throughout time. Stories, traditions, and even monuments centering around the sun can be found all over the globe. In fact, sunlight was so important to the Neolithic people that historians believe the winter solstice is what inspired them to build Stonehenge.

This enormous rock structure looks almost haphazardly designed at first glance, but the placement of the stones is anything but random. The Neolithic community at Stonehenge specifically set the structures up to frame the sunset during the winter solstice, as well as the sunrise during the summer solstice.

Archaeological evidence also suggests that large feasts were traditionally held at Stonehenge during the winter solstice. Recent excavations have uncovered the bones of cattle and pigs that were slaughtered approximately nine months after they were born in spring. All of this evidence adds up to indicate that, as far back as 3000 B.C., the winter solstice was a time when communities came together to celebrate with ceremonies and feasts.

Although the largest stone frame isn’t standing anymore, the winter solstice sun would once have aligned perfectly between these stones as it was setting. To this day, people still gather at Stonehenge on the winter solstice. Entry is free, and the site opens at sunrise so that revelers can witness the first glimpse of sunlight over this historic monument on the shortest day of the year.

Traditionally, Many Cultures Believed Evil Spirits Roamed the Earth During This Long Night

Since the winter solstice marks the longest night of the year, it’s no surprise that cultures around the world have developed folklore about it. More specifically, many stories center around spirits roaming through the December darkness. In Austria, for instance, the character of Krampus was built around Germanic solstice folklore. This half-demon, half-goat creature is the evil counterpart to Santa Claus — he roams the streets at night, punishing naughty children. Krampus has become a popular figure in pop culture, even inspiring a holiday-themed horror film in 2015.

However, Krampus’s popularity reigns supreme in Austria, where an annual Krampus Run is held in December. During this event, volunteers dress in fur suits, nightmarish masks, and horns. Then they run through the gathered crowds in full costume, jumping over gates and charging at festival-goers. This event is incredibly popular, and it is traditionally believed to ward off other evil spirits that may emerge during the solstice.

Europe is far from the only place with this sort of folklore. In Iran, the ancient celebration of Yalda falls on the winter solstice and celebrates the triumph of light over dark. While the festival itself is a celebration, it contains certain customs — known as Shab-e Chelleh — which are designed to protect people from evil. Revelers were traditionally advised to stay awake all night, so they’d gather with loved ones and eat summer fruits such as pomegranates and watermelons.

It Is the Inspiration for Religious and Secular Traditions in Cultures All Around the World

You probably know that the winter solstice inspired many familiar holiday traditions — but you may be surprised to learn the amount of influence this event has held over customs around the world. In China, for example, the winter solstice marks the beginning of the Dong Zhi festival. Dong Zhi celebrates the end of the harvest season and the return of sunlight. Families gather to feast. Traditional meals include tang yuan, or rice balls.

Known locally as Toji, the winter solstice in Japan comes with a particularly cute tradition: hot citrus baths with capybaras. These adorable rodents love the hot springs, which are traditionally infused with yuzu fruit to boost bathers’ immune systems and reduce itchy dry skin. People celebrating the solstice also eat kabocha, a winter squash that would have traditionally been available during the winter months.

In the U.S., the Hopi people celebrate an annual solstice ceremony called Soyal. This ceremony celebrates the sun’s return to summer. The festivities include prayers, ritual dances, storytelling, singing, and gift exchanges. In advance of the solstice, members of the community will often make prayer sticks and kachina dolls to represent nature spirits.

In Chichicastenango, Guatemala, the Santo Tomás festival is held every year during the week leading up to the winter solstice. This is a distinct shift from the traditional Catholic calendar, which holds the St. Thomas feast in July. In fact, Chichicastenango has blended Catholic beliefs into the indigenous Mayan calendar, which holds solstice celebrations during December. The Santo Tomás festival features a large feast, brightly colored clothing, a parade, fireworks, and music. People also perform a “flying pole” dance, in which participants bungee jump off the top of a 100 foot pole.

It’s Actually a Time, Not a Day

Although the winter solstice marks the shortest day and longest night, the term itself refers to a specific astronomical moment. In fact, the word “solstice” comes from two Latin words: sol, meaning “sun,” and sistere, meaning “to stand still.” The winter solstice occurs at the exact moment when the sun enters the Tropic of Capricorn. Because of the angle of the earth’s tilt, the sun appears to stand completely still during this moment.

The exact time of the winter solstice changes every year, but it always marks the official beginning of winter — just as, in June, the summer solstice marks the official beginning of summer. After the summer solstice, the sun gets steadily lower and lower in the sky as the earth tilts away from the sun. Once the winter solstice has taken place, the sun remains low in the sky for several days. Then, as the earth begins to tilt again, the sun gradually rises higher in the sky. Also, the days get longer before finally peaking at the summer solstice once again.