Sunset on the Winter Solstice at the Majorville Medicine Wheel archaeological site in southern Alberta, photographed in 2014. This 5,000 year old cairn and stone circle and a smaller cairn on a hilltop about a kilometre away are in perfect alignment with the setting sun on the day of the winter solstice.
You need a very capable 4x4 vehicle (and a bit of luck) to access this remote site during the winter. The hilltop location is completely exposed to the cold prairie winds, and it's remarkable to think of how many winters the First Nations peoples would have spent here watching the sun rising and setting to identify and then move all these large stones to mark out the precise orientation of the sunset on the shortest day of the year.