Yeah, it’s one massive ruin.
Spectators did not experience the interior of the Flavian Amphitheatre as anything like this. There was finish—cladding (mostly travertine) on the walls, staircases and access archways, statuary to remind visitors of gods and men (and probably goddesses and women), and most of the surface you see here was really seating, aisles, and arched entries. There was a cloth shade-cover that could be unfurled. So, no, it didn’t look like this. It’s like a skeleton compared to a living body. (Sorta.)
Drawing from several sources, this is what I conclude…. Spectators entered for free with tickets specifying a seating area, and some events lasted for days. The inauguration, in AD 80, lasted for 100 days, and later the stage area was modified so it could be flooded and used for nautical battles. A typical spectacle began with a morning opening parade (pompa), followed by fights between wild animals, hunts by armed men of animals, and shows of tamed animals. The experience of the latter was augmented by stunning scenes of their wild habitats. There was a break midday, used for executions. The goriest were damnatio ad bestias, in which the condemned were torn apart by wild animals. There’s no evidence that Christians were punished here in this manner. Between the major events, people played gambling games and postured to impress. [I tried a vertical panorama, an experiment; since the camera/phone can tell what's "up" I didn't know if it'd work—it did! The distortion is interesting, bowing the very vertical walls.]
Regarding the spectacles in the Colosseum, Claridge (2010:317–318) notes:
Gladiatorial shows were called munera (dutiful gifts) and were always given by individuals, not by the State. By the time the Colosseum was built they were being held as a regular public event, in December, as part of the New Year ritual, coinciding with the yearly political cycle, when they would be paid for by the incoming magistrates. At other times they could accompany the funerary rites for major public figures, or could be held on the anniversaries of past deaths. They were also staged in celebration of military triumphs. Such was their popularity that from the reign of Domitian it was decreed that in Rome they could only be given by the emperor; and elsewhere they required his sanction. The daily programme was usually divided into three parts: wild animal hunts (venationes) in the morning, public executions at midday, and gladiatorial contests in the afternoon; shows could run for many days depending on the available number of animals and gladiators. Trajan is said to have celebrated his Dacian triumph in AD 107 with 11,000 animals and 10,000 gladiators in the course of 123 days. Gladiators were a mixture of condemned criminals and prisoners of war (who were generally expendable), and career professionals (slaves, freedmen, or free volunteers), mostly men but occasionally women, specialized in different types of armour and weaponry: the heavily armed Myrmillo (named after the fish on his helmet) and the Samnite both had large oblong shields and swords; the more lightly armed Thracian, a round shield and curved scimitar; the Retiarius only a net and a trident. Others fought from chariots (essedarii), or on horseback. The fights were often staged in elaborate sets, with movable trees and buildings; the executions might involve complicated machinery and torture; some acted out particularly gruesome episodes from Greek or Roman mythology. Animals for the venationes came mainly from Africa and might include rhinoceros, hippos, elephants, and giraffes, as well as lions, panthers, leopards, crocodiles, and ostriches.
An observation: Romans use rear balconies like back porches, for storage and not-quite-so-public activities. Of course, it hosts plenty of drying laundry, plus often hot-water heaters are on the walls, piping the hot water inside—they’re the boxes on the walls. Here’s what I’ve been chuckling about: people store ladders there. Apparently, with high ceilings, people need ladders once in a while, and there is no “ladder for the building” or ladder that can be rented out from a nearby business. So many apartments have a ladder, and the place to store it is on the rear balcony (there’s one above the gate leaning next to the water heater).
An hour on a Friday afternoon…: we took a break using seating framing the church entry area part of the Piazza in front of the Chiesa di San Salvatore in Lauro, north of where we used to stay. We discovered several things. We saw two nursing moms take a break down from us on the same seating, each to feed their young-un while Pops idly stood by the stroller. No modesty cloths, just doing what needs doing. We also enjoyed the children playing out front, hopscotch and a bit of soccer-ball footwork. Then, at 5:30, the church bells began pealing, and Friday evening mass got underway. Music emanated. The kids kept playing. Then, just before 6, a procession formed in the doorway to the left of the church door. In the front were fully adult men carrying the cross and I don’t know what else—they make altar “boys” old here…. The group emerged and made a loop into the church, with the somewhat tottering highest-ranking fellow (judging by the tall headdress) at the end with two flanking attendees. No one told the little boy to stop and pick up his soccer ball, but he did. He was much more focused on the ritual than the group of girls. What you don’t see is that two of the nannies watching the kids looked like middle-aged Filapina ladies. Behind the officials, several toursts surged in, drawn by the pomp. We kept sitting and watching.
Claridge, Amanda, 2010. Rome: An Oxford Archaeological Guide. 2nd ed. Oxford University Press, Oxford.