The Pantheon in Rome, Italy

Twice destroyed and twice rebuilt, the Pantheon in Rome evolved into a domed building so famous that it inspired architects for 2,000 years.

What is the Pantheon in Rome?

Illustration of the Pantheon in Rome, During the Roman Empire

Today a Christian church, the Pantheon is the best preserved of all ancient Roman buildings and has been in near-continuous use since Hadrian’s reconstruction. From a distance the Pantheon is not as awe-inspiring as other ancient monuments — the dome appears low, not much higher than surrounding buildings. Inside, the Pantheon is among the most impressive in existence. Its inscription, M·AGRIPPA·L·F·COS·TERTIUM·FECIT, means: Marcus Agrippa, son of Lucius, consul for the third time, built this.

History of Pantheon in Rome

Model of the Pantheon in Rome, as it Appeared during the Roman Empire

The Pantheon in Rome was not built in a day. Twice destroyed and twice rebuilt, Rome's famous "Temple of All the Gods" began as a rectangular structure. Over the course of a century, this original Pantheon evolved into a domed building so famous that it inspired architects for the next 2,000 years.

Archeologists and historians debate which emperor and which architects designed Pantheon we see today. In 27 AD, Marcus Agrippa, the first emperor of the Roman Empire, commissioned a rectangular Pantheon building. Agrippa's Pantheon burnt down in 80 AD. All that remains is the front portico.

Nighttime view of the lighted Roman Pantheon from Piazza della Rotonda in Rome, Italy

Another Roman Emperor, Titus Flavius Domitianus, (or, simply Domitian) rebuilt the Pantheon, but it burned down in about 110 AD.

Then, in 126 AD, Emperor Hadrian completely restored the Pantheon in Rome. This Roman Pantheon survived many centuries and wars. The Pantheon remains the best-preserved building in Rome.

Architecture of the Pantheon

Diagram of the Pantheon in Rome, Showing the Interior Architecture

The identity of the architect behind the Pantheon is unknown, but most scholars attribute it to Apollodorus of Damascus. The parts of Hadrian’s Pantheon are a columned porch (8 massive granite Corinthian columns in front, two groups of four behind), an intermediate area of brick, and finally the monumental dome. The Pantheon’s dome is the largest surviving dome from antiquity; it was also the largest dome in the world until Brunelleschi’s dome on the Duomo of Florence was completed in 1436.

The Amazing Dome at the Roman Pantheon

The Ancient Romans were skilled at concrete construction. When they built the Pantheon around 125 A.D., the skilled builders of Rome applied advanced engineering to the Greek classical orders. They gave their Pantheon massive 25-foot thick walls to support a huge dome made of solid concrete. As the height of the dome rises, the concrete was mixed with lighter and lighter stone material; the top is largely pumice. With a diameter that measures 43.4 meters, the dome of the Roman Pantheon ranks as the world's largest dome made of unreinforced solid concrete.


The ceiling of the Pantheon dome has five symmetrical rows of 28 coffers (sunken panels) and a round oculus (opening) at the center. Sunlight streaming through the oculus illuminates the Pantheon rotunda. The coffered ceiling and oculus were not only decorative, but lessened the weight load of the roof.

The Pantheon and Roman Religion

Hadrian seems to have intended his rebuilt Pantheon to be a sort of ecumenical temple where people could worship any and all gods they wished, not just local Roman gods. This would have been keeping with Hadrian’s character — a widely travelled emperor, Hadrain admired Greek culture and respected other religions. During his reign an increasing number of Roman subjects either didn’t worship Roman gods or worshipped them under other names, so this move made good political sense, too.

Interior Space of the Pantheon:

The Pantheon has been called a “perfect” space because the diameter of the rotunda is equal to that of its height (43m, 142ft). The purpose of this space was to suggest geometrical perfection and symmetry in the context of a perfect universe. The interior space could fit perfectly either in a cube or in a sphere. The massive interior room is designed to symbolize the heavens; the oculus or Great Eye in the room is designed to symbolize the light- and life-giving sun.

Oculus of the Pantheon:

The central point of the Pantheon is far above visitors’ heads: the great eye, or oculus, in the room. It looks small, but it’s 27ft across and the source of all light in the building — symbolic of how the sun is the source of all light on earth. Rain that comes through collects in a drain in the center of the floor; the stone and moisture keep the interior cool through the summer. Every year, on June 21st, the rays of the sun at the summer equinox shines from the oculus through the front door.

Construction of the Pantheon:

How the dome has been able to bear its own weight has been a matter of great debate — if such a structure were built today with unreinforced concrete, it would quickly collapse. The Pantheon, though, has stood for centuries. No agreed-upon answers to this mystery exist, but speculation includes both an unknown formulation for the concrete as well as spending a lot of time tamping the wet concrete to eliminate air bubbles.

Changes in the Pantheon:

Some lament the architectural incoherence in the Pantheon. We see, for example, a Greek-style colonnade on the front with a Roman-style interior space. What we see, however, is not how the Pantheon was originally constructed. One of the most significant changes was the addition of two bell towers by Bernini. Called “asses’ ears” by Romans, they were removed in 1883. In a further act of vandalism, Pope Urban VIII had the bronze ceiling of the portico melted down for St. Peter’s portico.

Pantheon as a Christian Church:

One reason why the Pantheon has survived in such remarkable shape while other structures are gone may be the fact that Pope Boniface IVI consecrated it as a church dedicated to Mary and the Martyr Saints in 609. This is the official name which it continues to bear today and masses are still celebrated here. The Pantheon has also been used as a tomb: among those buried here are the painter Raphael, the first two kings, and first queen of Italy. Monarchists maintain a vigil at these latter tombs.

Influence of the Pantheon:

As one of the best surviving structures from ancient Rome, the influence of the Pantheon on modern architecture almost cannot be underestimated. Architects from all over Europe and America from the Renaissance through the 19th century studied it and incorporated what they learned into their own work. Echoes of the Pantheon can be found in numerous public structures: libraries, universities, Thomas Jefferson’s Rotunda, and more.

It’s also possible that the Pantheon has had an impact on Western religion: the Pantheon appears to be the first temple built with general public access in mind. Temples of the ancient world were generally limited only to specific priests; the public may have taken part in religious rituals in some fashion, but mostly as observers and outside the temple. The Pantheon, however, existed for all the people — a feature which is now standard for houses of worship in all religions of the West.

Hadrian on the Pantheon in Rome

Illustration of the Inside of the Pantheon in Rome, as a Christian Church

Hadrian wrote about the Pantheon he had reconstructed: “My intentions had been that this sanctuary of All Gods should reproduce the likeness of the terrestrial globe and of the stellar sphere...The cupola...revealed the sky through a great hole at the center, showing alternately dark and blue. This temple, both open and mysteriously enclosed, was conceived as a solar quadrant. The hours would make their round on that caissoned ceiling so carefully polished by Greek artisans; the disk of daylight would rest suspended there like a shield of gold; rain would form its clear pool on the pavement below, prayers would rise like smoke toward that void where we place the gods.”
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Posted in: Architecture, Heritage Architecture