Across time, people have marked the changes of seasons—sometimes in dramatic ways! Read about these ancient seasonal markers:
Every year on the summer solstice, thousands of people travel to Stonehenge, England, a place with huge stones that were arranged in a circle around 3000 B.C.
The huge monument celebrates the relation between the Sun and the seasons. See photos and historical details on the Stonehenge Web site .
At what is now Chichen Itza ("CHEE-chen-EET-sa"), Mexico, Mayans built a huge pyramid around the year A.D. 1000. The play of the Sun's light on it signals the beginning of the seasons.
On the spring equinox, for example, the light pattern looks like a snake. Mayans called this day "the return of the Sun serpent."
See more photos of this incredible pyramid at the Chichen Itza Web site. 
In today's Chaco Canyon, New Mexico, Anasazi Indians, who were expert sky watchers, carved spiral designs into rock to track the seasons and record the passage of time.
In this canyon is a petroglyph called the Sun Dagger because of the way the Sun's wedge-shape beams strike it in midday during the summer and winter solstices. See virtual movies of the Sun Daggar and other beautiful sites .
Around 3200 B.C., ancient people in Ireland built a huge mound of dirt and surrounded it with stones. Today, the knoll is called Newgrange.
For five days over the winter solstice period, a beam of sunlight illuminates a small room inside the mound for 17 minutes at dawn. The room holds only twenty people at a time.
Every year, thousands enter a lottery in hope of being one of the hundred people allowed to enter. See photos of Newgrange .
There are many ancient sites around the world. We welcome your comments about other ancient sites—and how you mark the seasons!