Pantheon

The Pantheon: Built by a Modest Emperor Who Kept Someone Else’s Name on It

The inscription across the Pantheon’s facade reads “M. AGRIPPA L. F. COS TERTIUM FECIT” – “Marcus Agrippa, son of Lucius, built this in his third consulship.” The building you are looking at was not built by Marcus Agrippa. Agrippa’s original temple on this site dated to 27 BCE and burned down. What stands was constructed around 125 CE under Emperor Hadrian – a complete rebuild on the same location. Hadrian, who commissioned it, kept Agrippa’s name on the facade rather than his own. This unusual modesty confused historians for centuries; the attribution to Agrippa was accepted as fact until excavation evidence finally clarified the timeline in the modern era.

The building is the best-preserved structure from classical antiquity and arguably the most influential in western architectural history. Brunelleschi measured it before designing the Florence Cathedral dome. Michelangelo measured it. Thomas Jefferson copied its proportions for the University of Virginia Rotunda. It is still in active use as a church. It is, in summary, a building that rewards knowing what you are looking at.

What to Actually Look At

The exterior is approached through a porch of sixteen Corinthian granite columns – the largest monolithic granite columns surviving from antiquity. The bronze doors (twelve tonnes, four metres high) are Roman originals. Cross the threshold and the interior does the thing photographs cannot capture.

The concrete dome spans 43.3 metres. The interior height from floor to the apex of the central opening equals exactly 43.3 metres. The building is a perfect sphere inscribed in a cylinder. The Romans lightened the dome by using coffers that reduce in size as they rise, and by mixing volcanic pumice and lighter aggregate near the top while using denser stone at the base. The oculus at the centre is nine metres in diameter and open to the sky. On a sunny day, a shaft of light moves across the interior as the earth turns. When it rains, the water falls through, hits the slightly sloped and channelled marble floor, and drains. The Roman engineers thought of everything except, apparently, the tourists.

The floor is original Roman paving (or very close to it) in geometric marble panels. The niches around the walls originally held statues of the seven planetary deities. Now they contain Christian altars and two royal tombs: Raphael, buried here by his own request in 1520, and the first two kings of unified Italy.

At Pentecost every year, rose petals are dropped through the oculus from above – one of those traditions that seems to have been invented for Instagram but predates Instagram by several centuries.

Admission and Timing

The Pantheon charges 5 euros admission through June 30, 2026, when the fee increases to 7 euros. Timed entry tickets are available via the official Musei Italiani portal or at the entrance. The first Sunday of each month is free admission, which predictably means significant crowds.

Arrive at 9am opening for manageable crowds and the best morning light through the oculus. By mid-morning in summer the building fills. There is a dress code (no shorts above the knee, shoulders covered) and a noise policy that is aspirationally enforced.

Around the Pantheon

The Piazza della Rotonda immediately outside has permanently elevated-price cafes. Sant’Eustachio il Caffe, three minutes’ walk away on Piazza Sant’Eustachio, is arguably the most serious coffee bar in Rome and worth the minor detour. The espresso is made with a proprietary roast and served pre-sweetened unless you specify; their caffe speciale is the signature.

Piazza Navona is ten minutes west. Campo de’ Fiori is fifteen minutes south – the morning market (7am to 2pm, closed Sundays) is an authentically Roman food market at prices that bear little resemblance to the Pantheon piazza.

For accommodation, the hotels immediately adjacent charge for proximity. Staying in Monti or Trastevere (better restaurants, better prices) and walking 20 to 25 minutes is the more sensible approach.