The dwellings of prehistoric Native North Americans are amongst the hardest archaeological structures to find and characterise – they leave only a shallow ring of stones. But the authors show that, when recorded to modern levels of precision, these tipi-stances contain a wealth of information. The stone rings are mapped in detail by hand, and located by GPS, their hearths are located by fluxgate survey and sampled for radiocarbon dating, and the results displayed in layered maps on GIS. Different social groups had different floor plans, so that, even where artefacts are missing, the movement of peoples can be dated and mapped. The results also bring to the fore the great cultural value of these, the dominant monument types of Bighorn Canyon National Recreational Area.