We were slow getting up the next day, after our exertions through ancient Rome, but we were able to get ourselves fed and over to the Piazza Navona slightly before noon, and struck out due east for the Pantheon.

The Pantheon is an ancient Roman building which was dedicated to all of the gods of the time. It is circular in shape, so as not to show preference to any particular god (this might have upset the others, as Roman gods were famously temperamental). The building was built somewhere around 126 A.D. There is a prominent inscription on the front explaining that it was built by the consul Marcus Agrippa, but this is untrue. It was completed by the emperor Hadrian, possibly from an original design by Trajan's architect Apollodorus of Damascus. An original Pantheon was built on the spot by Marcus Agrippa in 27 B.C., however. There are differing opinions as to what it looked like, but it was almost certainly very different from the current structure. It burned down in 80 A.D., and was replaced by another structure which also burned down, in 110 A.D, to be rebuilt by Hadrian. The Byzantine emperor presented the Pantheon to Pope Boniface IV in 609 A.D., at which time it was converted to a church honoring the Virgin Mary and all of the martyrs. This helped to protect the building from scavenging, but only partly – bronze which had covered the dome and the roof of the portico were stripped off over the centuries for other uses, as was much decorative exterior marble. The interior has been left mostly intact, though with some additions.



After gazing at the exterior for a number of minutes (it remains impressive, even without the missing decorations), we walked down to see the interior (there is no entrance fee - something free in Rome!). It quickly became obvious that it might have been a good idea to arrive earlier, as the tourist density was considerable.

The most striking thing on entering is the dome, which is immense. With a diameter of 142 feet, it was in fact the largest dome in the world, from the time it was built until Brunelleschi built his dome in Florence in 1436. It remains the world's largest unreinforced concrete dome. Unlike the Florence dome, it is hemispherical in shape, and if one were to add a "southern hemisphere", the result would be a gigantic globe sitting exactly on the ground. At the top is a hole called the oculus, which lets in light during the day. From the ground the hole doesn't look that big, but it's actually 27 feet in diameter. Being that big, it also lets in a fair amount of rain, but the clever Romans thought of this, embedding a drain in the center of the floor. The most difficult engineering challenge in building a dome is the handling of the extreme weight (the Pantheon's dome weighs about 5000 tons). The Romans took measures to reduce this weight, first by adding the oculus (which weighs nothing), and then by varying the thickness of the dome wall, from about four feet near the oculus to about 21 feet where the hemisphere meets the equator. They also used less dense material in forming the concrete near the top. Finally, a pattern of embedded square recesses (called coffers) was used, which reduced the weight and was also quite decorative. The walls holding up the dome are 21 feet thick, and are full of "blind arches", which look like bricked-in windows, to distribute the weight.


Down closer to the ground, it was possible to see a great deal of artwork, if one could find a path through all the bodies. There was also an altar and a section of pews, as the Pantheon is a church.


We worked our way around the perimeter, looking at all the paintings and sculptures.





We also noted the several tombs of those buried in the Pantheon. Among others, these long-term residents include Victor Emmanuel II (the first king of Italy, subject of the gigantic monument near the Forum), Umberto I (the second king, who was assassinated by an anarchist in 1900) and the Renaissance painter Raphael.



After a time, we emerged from the Pantheon and continued east in search of further adventure.