In this paper, we discuss the astronomical orientations in the city plans of Teotihuacan and Tenochtitlan. Mesoamerica exhibits much archaeoastronomy and these two sites are rich examples. Both exhibit alignments for solar horizon events that are integral in deliberate calendrical systems. The logic of these systems is shown, and this demonstrates that these cities were carefully planned with astronomical knowledge.

Review of the Skyscape Archaeology Keynote Lecture Series – Season Two: 2021–2022

At the great city of Tikal, the ancient Maya placed and oriented their ceremonial architecture and monuments in accordance with cosmological principles. Its earliest ceremonial plaza, the Mundo Perdido, is one of the oldest pre‐Classic E‐Groups of the Petén, the astronomical utility of which has been a topic of debate by archeologists and archaeoastronomers alike over the past century. In 1988, Aveni and Hartung surveyed the great temples of Tikal and revealed the relationship between their astronomical and dynastic aspects. Yet, over the intervening decades breakthroughs in the decipherment of the Maya glyphs have greatly increased our understanding of Tikal's dynastic history while interpretations in the field of archaeoastronomy have become more rigorous. For instance, more recent surveys and interpretations by Ŝprajc (2021a, 2021b) have demonstrated the importance of the Maya ritual calendar in the placement and orientation of ceremonial public architecture. The aim of this paper is to reassess this earlier fieldwork in archaeoastronomy, provide recent corroborative measurements of the orientation of key buildings, and provide a cohesive summation of the cosmological principles found in the design and construction of the city of Tikal.