America's Stonehenge - Salem
The ruins of "America's Stonehenge," a 4,000-year-old man-made structure, is comprised of rock walls, chambers and monoliths that create an accurate astronomical calendar. These monoliths mark important dates such as the equinoxes and solstices and point out the True North Alignment. It is believed by some that Stonehenge, which used to be called "Mystery Hill," was built by the Celts. Others believe that the ancient site was a Native American ceremonial meeting place.