As with many modern celebrations, ancient festivals observing the winter solstice merged with newer traditions to create the holiday season as we know it today.
Certain stones in the ancient circle line up with the midsummer sunrise and the winter solstice sunset, marking the longest and shortest days of the year.
It's based on Earth's position in relation to the sun and the 21st is when we'll see the winter solstice, the shortest day of the year when astronomical winter begins.
It falls at the midpoint between the winter solstice and the spring or vernal equinox, making it the ideal time to consider when springtime might finally come.
Historically on Dongzhi day, people went to the clan tombs to offer food and drink to their ancestor's spirits, clean the tombs, and work to maintain them.
According to legend, during the midwinter feast 2,500 years ago, the King of Wu was disgusted with all kinds of costly foods and wanted to eat something different.
As early as the Zhou Dynasty (c.11th century-256 BC), people worshipped the gods on the first day of the Winter Solstice, which also was the first day of the new year.
China has developed an unique festive food culture throughout the years. Eating dumplings is a common folk custom for many Chinese on the day of winter solstice, especially those living in the north.