At 9,642 feet on Medicine Mountain in the Bighorns lies a rim of white limestone 80 feet across with 28 spokes running to the centre and seven stone cairns set around it. A carbon sample from one cairn suggests the middle of the eighteenth century, but that is a minimum: the wood could have lodged there long after the wheel was laid. In 1972 the astronomer John Eddy showed it tracks the summer solstice sunrise and sunset and the heliacal risings of Sirius, Aldebaran and Rigel, which together give you a working calendar for the short mountain summer. The Crow say it was already here when they arrived. Several nations hold it sacred and no group has publicly claimed to have built it. National Historic Landmark since 1970. It is a high, seasonal, unpaved road and a walk in from the gate; treat it as an active place of worship, because it is one.
Bighorn National Forest, Wyoming
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