In the Pantheon in Rome the rays of the Sun enter from the central oculus and at noon illuminate the upper part of the dome on Winter Solstice (December 21), the grate above the large entrance door on the Equinox (March 21 and September 23), the center of the door on the Dies Natalis Urbis Romae (April 21) and finally the floor on Summer Solstice (April 21). But there is another extraordinary luminous phenomenon, the Arch of Light which perfectly matches the barrel vault above the door and occurs on April 7th and September 4th. The last results of this study are published in the new bookof Marina De Franceschini and Giuseppe Veneziano: "Pantheon Architecture & LIght" https://rirella-editrice.com/schedashop.aspx?idArt=2890&desc=PANTHEON.%20ARCHITECTURE%20&%20LIGHT

The Pantheon is one of the most important architectural monuments of all time. Thought to have been built by Emperor Hadrian in approximately 125 AD on the site of an earlier, Agrippan-era monument, it brilliantly displays the spatial pyrotechnics emblematic of Roman architecture and engineering. The Pantheon gives an up-to-date account of recent research on the best preserved building in the corpus of ancient Roman architecture from the time of its construction to the twenty-first century. Each chapter addresses a specific fundamental issue or period pertaining to the building; together, the essays in this volume shed light on all aspects of the Pantheon's creation, and establish the importance of the history of the building to an understanding of its ancient fabric and heritage, its present state, and its special role in the survival and evolution of ancient architecture in modern Rome.

«The item under review may surprise habitual readers of the BMCR: with its slim text and colorful appearance, it may resemble a brochure rather than a regular book. Yet some important information in it is relatively unknown, such as a concise history of the building’s vicissitudes after the imperial period, the useful list of the depredations of its precious marbles through time, primarily by the Roman Popes (pp.18-23), and a photographic commentary truly worthy of attention» https://bmcr.brynmawr.edu/2022/2022.03.13/

rom the Contents: Preface; Part I. Introduction: 1. Preliminary Considerations; 2. Major Advances in Knowledge About the Pantheon; Part II. Roman Design and Construction: 3. Standard Design Procedures; 4. Concrete Construction; 5. General Sources of Design; 6. Specific Sources of Design and Construction; Pert III: Preliminary Design Phase: 7. The Site; 8. Structural Design; Part IV. Concretre Construction: 9. Lower Drum and Block; 10. Upper Drum and Block; 11. Dome; Part V. Embellishment: 12. Comparison of the Ordes: 13. The Porticoes; 14. Finishing; Conlusions.

This paper focuses on large domes' building techniques and use of geometric rules in the design and construction of religious structures. A quick excursus on the cultural heritage in Italy and abroad highlights how domes have been used almost exclusively in sacred architecture, rather than in civic buildings, for most of history. Born of the need to cover large spaces without facing with the encumbrance of vertical elements, the domed cover, ideal for places of worship crowded by hundreds of faithful, has assumed, over the centuries, a symbolic meaning to every religion. In fact, identifying the shape of a large dome in the urban landscape immediately means to recognize the sacredness of that place. The ancient Romans who believed in the gods, Christians, Hindus and Muslims, all used this very peculiar architectural element in churches or mosques to express a kind of spiritual symbolism and, as mentioned, the fact that the shape of the dome arises from a functional reason, it has over time got pushed aside. Furthermore, the circle is a geometric form that possesses a great symbolic force, generated by the idea that, having no beginning and no end, reflected perfection, the eternal, and also the heavens. In this perspective, drawing a circle both in the horizontal and vertical section, the ultimate paradigm for all monumental domes was the Roman Pantheon which, with its centrally placed "oculus" or "eye of heaven" proved to be a model for all other domes after it, retaining its position as the most ancient and well preserved dome in the world. Therefore, this article concentrates on the study of the Pantheon as an emblem and reference model for all monumental domes. By analyzing the "meaning" of its architectural design and its structural and geometric characteristics, the research dissects a comparison between similar large domes, similar to each other, such as that of St. Francesco di Paola in Naples and the Mosta Dome in Malta. The comprehension of these valuable architectural artifacts lies between the search for their original geometry and the identification of structural models through which their shape was defined, namely the geometric and proportional rules of the past.

In the decade of the 1960’s the remains of a large building were discovered, 65 m southeast of the Library of Hadrian in Athens. The temple-like construction with dimensions 87 m and 39 m was identified with the Pantheon built under Hadrian. Recent research in the Library of Hadrian discovered a number of architectural features that match the colossal size of the building. Column bases and drums, as well as fragments from the superstructure, mostly incorporated in second use in the Tetraconch building, allow for the reconstruction of the outer and interior orders and their association with the in situ remains. The raised panels in the ashlars of the masonry, together with the octastyle prostyle plan which was used only during Hadrian’s years confirm the suggested chronology. As the cella corresponds to the 8 columns of the facade, the interior width equals 32 m, making the ‘Pantheon’ of Athens the broadest known cella, appropriate for the worship of all gods. The article includes stylistic comparisons with other works of the Hadrianic repertoire and views the ‘Pantheon’ as the Athenian response to the Pantheon in Rome.

Until 1995, it was thought that the Pantheon of Augustus had the entrance on the south side in contrast to that of the next scheduled time of Hadrian, which has placed it in the north. The archaeological excavation executed by the Sovrintendenza Capitolina di Roma, under the supervision of P. Virgili, during 1995-97, have shown that the Pantheon of Augustus had almost the same plan that Hadrian had rebuilt later and that we can see today. Even the surveys, conducted during 2007-2009 on the Mausoleum of Augustus, inside and on the forecourt, allowed to advance new hypotheses about the ground plan of the monument and its rearrangement made by a successor of Augustus. In 1990, N. Lanciano published a reading of the Hadrian's Pantheon as a solar calendar that use the light entering from the oculus and scans the interior space, at solar noon, on Equinoxes and Solstices days, in addition to the April 21 birthday of Rome. These researches show the two buildings, Pantheon and Augustus' Mausoleum, have more formal and symbolic links than was supposed. With attention to contemporary written sources, issues arise: the orientation of the axes of the buildings and their distance; the organization of the squares on which they open; the geometry of the inner dome and hall of the Pantheon. The urban complex of Augustus includes also the monumental sundial, mentioned by Plinius and partially excavated by Buchner in 1979, and the Ara Pacis location and its function: the most recent researches lead to exclude some hypotheses still present in articles and in the web. In the modern reuse (1990) this obelisk is a gnomon in the above horizontal sundial.