This article reconsiders the possible statuary of the Pantheon in Rome, both in its original Augustan form and in its later phases. It argues that the so-called ‘Algiers Relief’ has wrongly been connected with the Temple of Mars Ultor and is in fact evidence of the association of the Divus Julius with Mars and Venus in the Pantheon of Agrippa, a juxtaposition which reflects the direction of Augustan ideology in the 20s b.c. and the building's celestial purpose. This triple statue group became the focus of the later Pantheon, and its importance is highlighted by the hierarchized system of architectural ornament of the present building.

In many of the “wonders” of our past, information about their meaning and scope has been encoded in the form of astronomical alignments to celestial bodies. Therefore, in many cases, understanding the ideas of the ancient architects turns out to be connected with the study of the relationship of their cultures with the sky. This is the aim of archaeoastronomy, a discipline which is a quite efficacious tool in unraveling the original projects of many monuments. This issue is briefly discussed here by means of three examples taken from three completely different cultures and historical periods: the so-called “air shafts” of the Great Pyramid, the urban layout of the capital of the Incas, and the design of the Pantheon.