With Stonehenge, there are many theories concerning its use. They range from UFO landing sites to advanced astronomical calenders. Interpreting its function is both an archaeological and an astronomical problem. In the beginning of Stonehenge's study, archaeologists were certain that the Druids built it for ceremonies and sacrifices. Also invalidated was the theory that Stonehenge was a burial ground for citizens high in the social and economic ladder, when archaeologists found no bones there. Some have said that it was also used as a scientific, massive, and accurate doomsday instrument, to caculate when disastrous eathquakes and massive tidal waves tsunamis would occur.
Today, instead of stonehenge, other tools are used like stone circles. They say that they're used 2 predict when bad weather is coming. Also, to tell time when the shadows of the sun change.