BRITISH AIRWAYS was justifiably proud of getting your correspondent from London to Rome only three hours behind schedule. After all, Heathrow had been in the grip of those freak snow conditions which traditionally leave Britain stunned with surprise.

All my previous visits to the Eternal City had been done on the cheap. In those days I was still traveling on the weird escape routes frequented by students. Some of the students turned out to be 80-year-old Calabrian peasant ladies carrying string bags full of onions. The charter aircraft belonged to semischeduled airlines.

I used to live in the kind of coldwater pensione on the Via del Corso where the original rooms had been partitioned not only vertically but horizontally as well, so that the spiral staircase beside your bed led up to a bare ceiling. You had to apply in writing to take a bath. Lunch was half a plate of pasta on the other side of the Tiber. Dinner was the other half.

But a lot of water has gone over the viaduct since then, and this time I was a bona fide traveler. Even at one o'clock in the morning Leonardo da Vinci airport, tastefully done out in fluted chromium, was a treat for the eyes. My hotel was in Piazza Trinita dei Monti at the very top of the Spanish Steps. The decor was strictly veneers and cut glass, but it was heavily tricked out with the Medici coat of arms and the bath came ready equipped not just with a plug, but a dinky sachet of foam-producing green goo. My waiting readers were subsidizing this luxury. Could I justify their confidence? What can you say about so old a city in so short a space? I sank cravenly into the foam.

Sleep allayed my fears, but they came back in the morning. I appeared on the Spanish Steps just in time to be greeted by the cold weather, which had been racing down Europe during the night. Rome suddenly froze up solid. The Triton, forever blowing his conch in the Piazza Barberini, abruptly became festooned with icicles. As unashamedly ostentatious as ever, the wealthier Roman women shopping in the Via Condotti instantly adopted a uniform -- mink and boots.

In a bar a little fat woman who looked like a bale of furs reached up to spoon the cream from a glass of hot chocolate higher than her head. For once nobody was in any danger of being kidnaped. Cold weather meant plenty of snow in the mountain resorts. The terrorists were all away skiing.

With only a few days at my disposal I decided to leave most of my usual haunts unvisited, apart from a quick trip to St. Peter's to see how well the Michelangelo "Pieta" had been repaired. Since I had last seen this masterpiece it had been attacked by a hammer-wielding Australian of Hungarian origins. Perhaps he was trying to effect improvements. Anyway, he had given the Madonna a nose job. The nose was now back on and the whole statue, I was glad to see, had been separated from its adoring public by a glass wall. Taking it for granted that none of my compatriots had been flicking ink darts at the Sistine ceiling, I headed out by car to the Catacombs.

Out on the old Appian Way it was as cold as Caligula's heart. Sleet drenched the roadside ruins. Like a leftover from La Strada, a lone prostitute solicited business from passing cars. A couple of millennia ago the cars would have been chariots but she would have looked roughly the same.

Hilarius Fuscus has a tomb out there somewhere. Apart from his name he is of no historical interest, but with a name like Hilarius Fuscus how interesting do you have to be? The Catacombs, however, were mainly for the nameless. In the Catacombs of Domitilla, for example, more than 100,000 people were buried, but only 70 of them came down to modern times with any identity beyond that conferred by the heap of powder their bones turned into when touched by air.

A Gelman monk took me down into the ground. "Zer soil is called tufa. Volcaning. Easy for tunnels. Mind zer head." In this one set of catacombs there are 11 miles of tunnels, one network under another. The two top levels have electric light throughout. "Mine apologies for zer electrig light. Mit candles is more eery. Zis way."

People had been filed away down here by the generation. Some of the frescoes remain intelligible. You can see the style changing through time: suddenly a Byzantine Christ tells you that the Empire of the West is in decline. The sign of the fish is everywhere. "You also see zer sign of zer turdle dove. Symbol of luff and pizz."

When we arrived back at the surface the good friar's next party was alighting from its coach -- a couple of hundred Japanese, all of them with cameras around their necks. Some of the cameras had tripods attached. I had been lucky to get what amounted to a private view. Nor were there many tourists at the newest of the Catacombs, the Fosse Ardeatine. The people buried here all died at once, on March 24, 1944, victims of an execution by Hitler's SS in reprisal for slayings by Italian Resistance fighters.

Everything and everywhere in and around is saturated with time. If you look too long, you will be hypnotized. I went out to Lago Albano in the Alban Hills. The lake is in a giant crater. High on the rim is a town called Marino, where Sophia Loren owns a house. The pope's summer residence is somewhere up there, too.

But take a close look at that sheltered lake. Imagine it in tumult. In Imperial times it was called Lacus Albanus and mock naval battles were held on it. That would have been my job in those days: writing reviews of mock naval battles. "Once again Hilarius Fuscus creamed the opposition..."

In Rome's Via Michelangelo Caetani a shrine of wreaths and photographs marks the spot where ex-premier Moro's body was dumped, mid-way between the respective headquarters of the Communists and the Christian Democrats. To the terrorists, Moro stood for compromise. It followed logically that his life was forfeit. Most of the terrorists are figli di papa -- sons of daddy. If daddy spends most of his time making money, shooting him is a good way of getting his attention. Under the absolutism there is petulance.

There have been bodies in the street before. As the Middle Ages gave way to the Renaissance, the Caetani fought the Colonna who fought the Orsini who fought the Caetani. Rienzo called himself Tribune and reunited Rome for a few days. The great families used the papacy to further their earthly ambitions. But ever since the fall of the old Empire the very idea of a renewed temporal hegemony had been an empty dream.

You don't have to go all the way out to the Alban Hills in order to look down on Rome and discover it to be a small place. All you have to do is climb the Aventine. What you can see from there is just about all there is. When Rome ceased to be the capital city of an international empire, it reverted to being a provincial town. Though it has been officially called so since 1870, it has never really become the capital of Italy -- not the way London is the capital of England or Paris of France. Rome produces little. For a long time it has been a consumer's town. Even the Renaissance was produced in Florence and consumed in Rome. Bringing Michelangelo to Rome was like bringing Tolstoy to Hollywood.

Rome is a good place for madmen to dream of building empires. It is a bad place from which to govern Italy. Mussolini chose the first option, with the inevitable consequences. The most recent of Rome's overlords, he left the fewest traces. Apart from the embarrassingly fine architecture of the EUR district out on the periphery, the city gives almost no indication that he ever lived. The Palazzo Venezia is, of course, still there. You can pick out the balcony from which he shouted to the crowds and the window behind which he left a light burning at night to encourage the notion that he never slept.

The city is left with nothing but its heritage. There is a lot to look after. Things get stolen, or just fall apart. In the Piazza Navona I found the Bernini fountains plump with ice, like overfilled tubs of lemon gelato . In a dark alley behind the piazza stands the little church of Santa Maria della Pace. On the outside walls are the usual political graffiti. Inside there are some sibyls by Raphael.

The doors are open only between 7 and 8:30 in the morning, for mass. Outside the portico, when I arrived, the body of a man was being hauled out of an abandoned car and loaded into a gray plastic bag. He was a tramp who had frozen to death in the night. A policeman signed for the corpse. Dirt, litter and decay. Raffaello Sanzio of Urbino was here once.

But it's unfair to Rome to let the weather get you down. In spring and summer the fountains ionize the air to the point that even the third-rate expatriate American writers who infest the city feel themselves brimming over with creative energy. Yet even then you can detect the weariness beneath the fervor. No less afraid of dying than anybody else, I still like the idea of what Lucretius describes as the reef of destruction to which all things must tend, spatio aetatis defessa vetusto -- worn out by the ancient lapse of years. But I don't want to see the reef every day.

The Spanish Steps were a cataract. Climbing them like an exhausted salmon, I passed the window of the room in which Keats coughed out the last hours of his short life with nothing to look at except a cemetery of time. No wonder he forgot his own vitality and declared that his name was writ in water. As he should have realized, the thing to do when you feel like that is to pack up and catch a plane to London. Which I did.