To those who look at a city and see not humanity but stone, Rome is overwhelmingly a city of worship. Rome has always been a pious place, sacrificing abundantly (if not always sincerely) to any and every god and hero who might become an ally in the dream of empire. Rome worships the gods; Rome gives adoration to the dead. Temples, altars, shrines, and statues abound. Incense may abruptly waft from any corner. One may step down a narrow winding street in a neighbourhood known since childhood and suddenly come upon a landmark never noticed before — a tiny, crude statue of some forgotten Etruscan god set in a niche and concealed behind a wild fennel bush, a secret known only to the children who play in the alley and the inhabitants of the house, who worship the forsaken and impotent god as a household deity. Or one may come upon an entire temple, unimaginably ancient, so old it is made not of bricks and marble but of worm-eaten wood, its dim interior long ago stripped of all clues of the divinity that once resided there, but still held sacred for reasons no one living can remember.

Other sights are more specialized to their region. Consider my own neighbourhood, with its odd mixture of death and desire. My home sits partway up the Esquiline Hill. Above me is the quarter of the morgue workers, those who tend the flesh of the dead — embalmers, perfume rubbers, stokers of the flame. Day and night a massive column of smoke rises from the summit, thicker and blacker than any other in this city of smoke, and carrying that strangely appealing odour of seared flesh otherwise found only on battlefields. Below my house, at the foot of the hill, is the notorious Subura, the greatest concentration of taverns, gaming houses, and brothels west of Alexandria. The proximity of such disparate neighbours — purveyors of death on one hand and of life's basest pleasures on the other — can lead to strange juxtapositions.

Tiro and I descended the paved footpath that dropped steeply from my front door, passing the blank plaster walls of my neighbours. 'Be careful here,' I told him, pointing out the spot where I knew a fresh load of excrement would be waiting, slopped over the wall by the inhabitants of the house on the left. Tiro skipped to his right, barely avoiding the pile, and wrinkled his nose.

'That wasn't there when I came up the steps,' he laughed.

'No, it looks quite fresh. The mistress of the house,' I explained with a sigh, 'comes from some backward little town in Samnium. A million times I've explained to her how the public sewers work, but she only answers: "This is the way we did it in Pluto's Hole," or whatever her stinking little town is called. It never stays long; sometime during the day the man who lives behind the wall on the right has one of his slaves collect the stuff and cart it off. I don't know why; the path leads only to my door — I'm the only one who has to look at it, and the only one likely to step in it. Maybe the smell offends him. Maybe he steals it to fertilize his gardens. I only know it's one of life's predictable routines — the lady from Pluto's Hole will throw her family's shit over the wall every morning; the man across the way will carry it off before nightfall.' I gave Tiro my warmest smile. 'I explain this to anyone who's likely to visit me between sunrise and sunset. Otherwise you're likely to ruin a perfectly good pair of shoes.'

The pathway broadened. The houses became smaller and drew closer together. At last we reached the foot of the Esquiline and stepped into the wide avenue of the Subura Way. A group of gladiators, heads shaved except for barbaric topknots, came staggering out of the Lair of Venus. The Lair is notorious for cheating its customers, especially visitors to Rome, but natives as well, which is one of the reasons I've never patronized it, despite its convenient proximity to my house. Cheated or not, the gladiators seemed satisfied. They staggered into the street grasping one another's shoulders for support and bellowing out a song that had as many tunes as there were voices to sing it, still drunk after what must have been a very long night of debauchery.

At the edge of the street a group of young trigon players broke and scattered to get out of the gladiators' way, then reformed to begin a fresh round, each taking his turn at the points of a triangle drawn in the dust. They slapped the leather ball back and forth, laughing loudly. They were hardly more than boys, but I'd seen them going in and out of the side entrance to the Lair often enough to know that they were employed there. It was a testament to the energy of youth that they should be up and playing so early, after a long night's work in the brothel.

We turned right, proceeding westward along the Subura Way, following the drunken gladiators. Another road descending from the Esquiline emptied into a broad intersection ahead. A rule in Rome: the wider the street or the greater the square, the more crowded and impassable it will be. Tiro and I were forced to walk in single file, threading our way through the sudden congestion of carts and animals and makeshift markets. I quickened my pace and called back at him to keep up; soon we caught up with the gladiators. Predictably, the crowd parted for them like mist before a heavy gust of wind. Tiro and I followed in their wake.

'Make way!' a loud voice suddenly called. 'Make way for the dead!' A cluster of white-robed embalmers pressed in upon our right, coming down from the Esquiline. They pushed a long, narrow cart bearing a body that was wrapped in gauze and seemed to float in a cocoon of fragrances — attar of roses, unguent of clove, unnameable Oriental spices. As always the smell of smoke clung to their clothing, mixed with the odour of burning flesh from the vast crematoria up on the hill.

'Make way!' their leader shouted, brandishing a slender wooden rod of the sort one might use to discipline mildly a dog or a slave. He struck nothing but empty air, but the gladiators took offence. One of them slapped the rod from the embalmer's hand. It flew spinning through the air and would have struck me in the race had I not ducked. I heard a squeal of painful surprise behind me, but didn't bother to look. I stayed low and reached for Tiro's sleeve.

The press of the crowd was too thick for escape. Instead of quietly turning back, as circumstances recommended, strangers were suddenly pushing in from all sides, smelling the prospect of violence and afraid they might miss seeing it. They were not disappointed.

The embalmer was a short man, pot-bellied, wrinkled, and balding. He rose to his full height and a little beyond, straining on tiptoes. He shoved his face, twisted with rage, against the gladiator's. He wrinkled his nose at the gladiator's breath — even from where I stood I caught a whiff of garlic and stale wine — and hissed at him like a snake. The sight was absurd, pathetic, alarming. The huge gladiator responded with a loud burp and another slap, this one knocking the embalmer backwards against the cart. There was a sharp crack of bone or wood, or both; the embalmer and the cart collapsed together.

I tightened my grasp on Tiro's sleeve. 'This way,' I hissed, indicating a sudden opening in the crowd. Before we could reach it the breach was filled with a crush of new spectators.

Tiro made a peculiar noise. I wheeled around. The noise was less peculiar than the expression on his face. He was looking downwards. There was a hard, heavy nudge against my ankles. The cart had spilled its contents onto the street. The body had rolled face-up against my feet, its gauzy shroud unwinding behind it.

The corpse was that of a woman, hardly more than a girl. She was blonde and pale, the way that all corpses are pale when drained of their blood. Despite the waxiness of her flesh, there was evidence of what had once been considerable beauty. The tumble had ripped her gown, baring a single breast as white and hard as alabaster, and a single nipple the colour of faded roses.