The Middle Woodland period Newark Earthworks in Newark, Ohio, are the largest known set of connected, geometrical earthworks ever constructed. An analysis of available evidence (survey, topographi- cal, statistical, and archaeological) shows that the geometry of this Hopewell complex and its relation to the surrounding terrain can be understood in terms of astronomical alignments to the Sun and Moon. The geometrical structure of the site is consistently aligned with extremes in the 18.6-year cycle of lunar standstills. An under- standing of the topographical context is presented by identifying four hilltops connected by lunar standstill alignments to long linear fea- tures of the Earthworks and connected to each other by alignments to the Sun at the solstices. The number and accuracy of the alignments together with Monte Carlo studies showing the low likelihood of chance producing such results suggest that Newark was aligned with unprecedented accuracy both to regional topographical features and astronomical phenomena. This article presents a new and extended analysis of available evidence per- taining to the hypothesis that prehistoric geometric earthworks at Newark, Ohio, were intentionally located and geometrically designed to incorporate accurate alignments to the major and minor lunar standstills. In earlier work (Hively and Horn 1982, 1984, 2006), we presented survey and statistical evidence to support this hypothesis. Here we present an analysis of new survey and topographic information that motivates a re-examination and re- fined interpretation of our earlier data. We believe that this analysis develops a strong case that the builders used observations from identifiable hills to discover and record an accurate knowledge of the motion of the rise and set points of the Moon during its 18.6-year regression cycle. We have also deter- mined that azimuth relationships between pairs of these hilltop observation