With more than seven million visitors per year, the Pantheon is one of Italy’s most-viewed monuments, but there are many interesting facts and legends surrounding this ancient Roman structure.
As old as the Pantheon is, it was not the first structure on that site. The original temple was built around 25 BC by Roman Consul Marcus Agrippa, whose name you can still make out on the façade. Archaeologists now believe his version was destroyed and rebuilt, possibly more than once. The building that now stands is attributed to Emperor Hadrian, who is thought to have had it redesigned and completed nearly 1,900 years ago.
The Pantheon’s age is all the more remarkable when you consider what astonishing skill went into creating its curved roof. You might not think so at first glance, but its dome is wider than the famous dome atop St. Peter’s Basilica by almost six feet; however, St. Peter’s dome rises much higher and carries far more weight.
At 143 feet in diameter, the dome remains the world’s largest unreinforced concrete structure of its kind. Its ancient architects cleverly lightened the weight of the roof, starting with thick travertine and bricks at the lower portion of the dome, followed by thinner terracotta tiles and then lightweight tufa and pumice at the top. At the highest point, the oculus – the 30 foot circular hole in the roof actually saves crucial weight at the dome’s most vulnerable point. The dome is also exactly as high as it is wide and the interior of the Pantheon would fit perfectly into a 143 foot diameter sphere.
One of the most common questions by tourists, especially children, involves the oculus. Everyone wants to know what happens when it rains. The simple answer is that some of the interior gets wet, but it never floods. Take a closer look at the paved floor and you will notice that some of the slabs have small holes running through them which allow any rainwater to drain through to sewers below.
What’s more, when the Pantheon was lit with candles in the past, there were so many that the flames produced an upwards current of warm air that would cause the vast majority of falling rain to evaporate before reaching the floor.
There are 16 granite columns that support the portico and they travelled thousands of miles to get to Rome. The granite was quarried in Egypt, in the mountains near the Red Sea. Each was then dragged to the Nile, sailed up the river, across the Mediterranean and along the Tiber before finally being pulled into place. Quite a journey, especially when you considers that each one weighs 60 tons.
While some of the external decoration of the structure was lost after the fall of the Empire, one part of the Pantheon was recycled – the bronze ceiling that once made the portico shine. The metal was stripped off on the orders of Pope Urban VIII in the 17th century and melted down to make the cannons for the Castel Sant’Angelo, the Papal fortress on the other side of the Tiber. Legend states that some of the bronze also ended up in the sculpted canopy over the altar of St. Peter’s. The travesty earned the Pope, a member of the illustrious Barberini family, the epithet: “What the barbarians didn’t do, the Barberinis did.”
The Pantheon, like many of Rome’s finest monuments, fell into disrepair during the ‘Dark Ages.’ Historians believe that as the ground level around it rose, dirt accumulated on the floor of the structure and clogged the drainage system. Water coming through the oculus allowed weeds and vines to grow and even trees put down roots so that for a time, trees grew inside the Pantheon. Based upon a request by the Pope in 609 AD, the Pantheon was cleaned up and turned into a Christian church. Although for almost 2,000 years it has been known by its Roman name, its actual title is Santa Maria della Rotunda.
Michelangelo said the Pantheon was so perfect it must have been designed by angels, not men; however, later architects still felt compelled to make some changes. In the 17th century, two bell towers were added on either side of the portico, disrupting the building’s classical outline. The towers were not especially esthetically pleasing, earning the nickname “the ass’s ears.” They were removed by general consensus in the 1880s.
The Pantheon is also the final resting place for many famous people and one who is not famous at all. It houses the tombs of one queen, two kings and nine artists, architects and musicians. But there is one much less famous grave belonging to Maria Antonietta Di Bibbiena. She was engaged to the master painter Raphael. The young noblewoman died before they were married and is buried to the right of her fiancée, who lies in what is arguably the building’s finest tomb.
On the Pentecost, the day the Holy Spirit descended on the Apostles, the Pantheon is the site of a spectacular ritual in which firefighters pour a shower of rose petals through the oculus. The red symbolizes the blood that Jesus Christ shed to save humankind. The ceremony is free of charge and open to all, but places are limited so arrive early and be prepared to wait on line. Alternatively, you can watch the live stream online each year.
Finally, if you are lucky enough to be inside the Pantheon on April 21 around noon, look towards the entrance. You will see the sunlight that enters through the oculus directly illuminates the door with a glow that can only be described as majestic. April 21 is the date of the founding of Rome and historians suspect that the Pantheon was designed to give the Emperor some gloriously symbolic backlighting as he entered the temple to celebrate the anniversary. Regardless of what day you visit the monument, it is a fantastic experience, hopefully made more so by the interesting facts that you can now divulge to others during your visit.