Nalanda, in eastern India's Bihar state, was once the most important Buddhist monastery in the world. The six excavated temples there are oriented approximately to the cardinal directions, but their east–west axes are tilted more than 4° south of east. Other key Buddhist temples within the same cultural milieu (Bodhgaya, Vikramasila, Somapura, and Samye) are similarly oriented a few degrees south of east. As M. B. Rajani and Viraj Kumarargue in Nalanda: A Tale in the Twist, this demands an explanation, because a method to orient structures to within 0.5° of the cardinal directions was known in the region for several centuries prior to the construction of these temples. Rajani and Kumar identify a temporal pattern in the orientation of Nalanda's temples; hypothesize that each temple was aligned with the rise of a specific star (Spica or Beta Librae), with the temporal pattern being a consequence of axial precession; propose a simple, unified explanation for the few exceptions to the pattern; and use this hypothesis to propose an approximate construction date for each temple based on its orientation.