This learning module introduces students to the following prehistoric structures created and used to mark time by following the movement of the sun and moon: a 3-slab rock structure found high on Fajada butte in New Mexico built by the Anasazi and termed the Anasazi Sun Dagger, and a more expansive site, the Kokino Megalithic Observatory, found in Macedonia. Activities include determining the altitude/azimuth of solar events, comparing anasazi building orientation to lunar and solar events, an