The Pantheon: Roman Architectural Marvel & Engineering Masterpiece
The Pantheon: A Testament to Roman Ingenuity
The Pantheon represents a significant advancement in Roman art, building upon Greek construction techniques. The Romans experimented with arches and aimed for monumentality. The Pantheon, with its massive dome constructed using materials pushed to their limits, stands as a masterpiece of Roman engineering. Its dimensions remained unmatched until the 19th century and the advent of iron architecture. The dome, seemingly modest from the outside, is breathtaking upon entering the interior.
General Information
- Name: Pantheon
- Architect: Unknown (Commissioned by Emperor Hadrian)
- Timeline: 2nd Century, between 118-125 AD
- Location: Champ de Mars, Rome
- Style: Imperial Roman
- Materials: Concrete, brick, wood, and marble
- Dimensions: 35m wide (frame), 18m high (columns), 58m external diameter (drum)
Exterior
Originally conceived as part of an imperial forum, the Pantheon was meant to be surrounded by an arcaded square, which was never fully realized. Only the entrance portico was visible. The portico (1), in line with Greek temples, is octostyle, featuring eight monolithic granite columns with white marble bases. These support an entablature inscribed with the name of the ancient temple of Agrippa. A transitional body (2) leads to the drum. The drum, now devoid of its marble and stucco coating, appears as a bare cylinder. Its structure combines concrete and brick, typical of Roman construction. Lines of fascia (3) identify three overlapping stories of brick arches, which act as buttresses on the wall, distributing the dome’s pressure to eight strategically placed pillars within the cella. The drum ends at the top (4), which was once covered with gilded bronze tiles but is now bare. The dome’s construction pushed materials to their endurance limits.
Floor Plan
The portico (1) is divided by columns into three naves. The central nave culminates in giant bronze doors leading to the cella, while the side aisles end in two niches. The transitional body was added to bridge the gap between the rectangular portico and the circular cella. The circular cella is dominated by eight pillars, which bear the dome’s weight. This load distribution allows for eight niches to be opened between the pillars around the cella’s perimeter.
Interior
The lower cylinder is a fictional facade constructed from high-quality materials. This grand and luxurious ornamental set serves a dual purpose: it conceals the load-bearing system and pays homage to Greek architecture. Above this illusion rises an attic with shuttered windows that provide indirect lighting to the niches below. The cupola penthouse (4) is at a height of 43.3m. A ring structure and a set of nerve compartments form the empty square coffers, which diminish in size as they approach the top, enhancing the room’s grandeur. The dome is crowned by an oculus, a round window almost 9m in diameter, protected by alabaster sheets. This oculus is the primary source of light and ventilation. The light filtering through the oculus emulates the solar disk, moving across the roof as the day progresses.
Significance
The Pantheon, a second reconstruction of the original, is a religious building dedicated to all gods, including previous emperors. It indirectly glorifies Emperor Hadrian. Its interior is a constant reference to Roman cosmology. The dome, for example, is divided into 5 circles, each with 28 coffers, symbolizing the days of the lunar month. It can also be interpreted as 5 concentric spheres of the ancient planetary system, with the sun at the center. The dome’s shape evokes the sky, illuminated by the sun, reflecting the Roman view of Rome as the center of the universe. The Pantheon has fascinated architects from the Renaissance and Baroque periods, influencing works such as the Pazzi Chapel, the dome of Santa Maria del Fiore by Brunelleschi, and San Carlo alle Quattro Fontane by Borromini.