The ruined Excubitorium, an ancient barracks for Rome's fire brigade, serves as a memorial to the city’s first responders.

The trams rumbling along Viale Trastevere wake me. The bell announcing morning prayers at S. Crisogono tolls a little later. Ponte Garibaldi is visible from the terrace and roofs stretch away to the distant onion dome of S. Andrea della Valle. The Tiber is in flood far upstream, but not here, and so it lies way below its high, canalised embankment. This bucolic setting in Rome bids any viewer to think it’s eternal. Outside, though, not all is as it appears from the terrace. The never-ending piles of rubbish attract rats that scrabble brazenly over the cobblestones. The pavements are crumbling, the only clean sections are being swept by enterprising migrants who invite pedestrians to pitch a coin into soup bowls beside signs in crude cursive. Everyone knows Rome is in crisis. House prices are going up, visitors arrive in droves to occupy a spiralling number of Airbnb rooms, but civic life in this eternal city is visibly waning. 
Excubitorium
Under my apartment block lies the ancient Roman fire-station – the Excubitorium - known as Corte VII. Although it is normally closed to the public, it is possible to get a permesso, and a kindly inspector from Rome’s superintendency will open it up. I cannot stress how worthwhile and thought-provoking these ruins are. Excavated in 1866 by Angelo Pellegrini on behalf of the Vatican, they remained open and uncurated until 1966. Sad to say, this 1966 roof is no longer trustworthy. Bits plunge into the excavated bowels of the fire station below, obliging us to only stand at the door and not enter. Still, it is an extraordinary sight if you let your imagination loose.
Constant vigilance
Ancient Rome’s fire service was set up by Augustus in 6 AD when the city’s population numbered an estimated million souls. The Excubutorium was the watch-house of the seventh cohort of the vigiles, the brigade that took care of the Transtiber (region XIV). The city’s brigade was composed of 3,920 men divided into seven cohorts of 560, each subdivided into seven centuries of 80 men. Each cohort had responsibility for two regions, with a watch-house in each where the men kept their kit. The vigili were constantly on the lookout for fires and were authorised to break into property to stop one from spreading. 
The Corte VII building was a brick-built town house dating from the second century AD that was transformed into a fire station at the end of the century. From the steps of today's ruins you look into a dark courtyard with a fountain in the centre. To the right is an elegant porticoed niche that for all the world looks like a door. In fact, it was for a shrine and faces a door on the left that leads into the two- or three-storey, multi-roomed fire-house. Benching followed the walls of the atrium. Red plaster once covered the benches and walls to conceal the brickwork, and, according to our guide, was vandalised by hundreds of graffiti made by the firemen as they whiled away their down-time. 
Excavations
Descending into this now anonymous excavation, the extent and complexity of life in ancient Rome at its zenith is nothing less than awesome. Did firemen from here cross the Tiber to fight the great 80 AD fire in the Campus Martius, seat today of the Crypta Balbi, the museum dedicated to Rome’s final centuries and the immediately following period?
Heading for “the Crypta”, as Italian archaeologists affectionately call it, my visit to the Excubitorium sets me thinking. I have recently been reading Kyle Harper’s Fate of Rome (2017), his spirited, provocative and well-written new book that almost, if not quite, attributes the decline of Rome to climatic conditions and the bubonic plague. 

In his faux thriller, Harper leads his readers smartly through Roman imperial history from Augustus to the seventh century. Cleverly, he inserts climatic change as a causal vector along the way. The fire-station under my apartment, it would now appear, was constructed during the Roman Climatic Optimum. Over this period the Mediterranean tessellation of micro climates enjoyed warm, wet and stable weather causing the Alpine glaciers to melt. The empire of Augustus and his immediate successors, according to Harper, was a fecund, giant greenhouse. This was what historian Edward Gibbon famously described as the “happiest age”. 
There were adverse consequences for Rome’s metaphorical soul, such as the river Tiber regularly breaking its banks, most often in late summer halcyon days. Pliny the Younger describes furniture floating through the streets. The Optimum ended in the Antonine period, in the second century AD, with a smallpox plague. Catastrophic late summer floods that doubtless engulfed the firemen in the Excubitorium, the breeding ground of infectious diseases like bacillary dysentery and malaria, were eclipsed by a smallpox pandemic that carried away as many as 150,000 of Rome’s citizens in mid-to-late 166 AD. It was, writes Harper, “a pathogen bomb”. 
Rome’s apocalypse?
Rome and its empire bounced back, of course. But by the fifth century civic management was in poor shape and probably led to the desertion of the Excubitorium. Worse followed, as Harper colourfully describes. Climatic change ushered in the Late Antique Little Ice Age, a period in the sixth to seventh centuries of cooling and winter storms causing extreme flooding in the capital, as well as colder climes. As if this wasn’t bad enough, a pernicious disaster struck in the form of a promiscuous killer, Yersinia Pestis, carried by an oriental rat flea. The pest arrived from the Indian Ocean and first devastated the cities of the eastern Empire. 

In the midst of a war between the Ostrogoths and Byzantium, traders and mariners unwittingly transported the flea to Rome, and in 542 AD it decimated the eternal city. As Harper says, the Colosseum, which had been spruced up for games in 520 AD, could by 590 AD and the new pontificate of Gregory the Great have easily accommodated the city’s surviving 10-20,000 residents in the fabled arena. (The lugubrious Byzantine historian, Procopius, estimated the city’s population plunged to a pitiful 500 citizens.) As Pope Gregory balefully noted, “the end of the world is no longer just predicted, but is revealing itself.” How many firemen survived, one wonders? 
Harper’s fateful view of Rome deserves our attention. There can be no doubt that the ancient metropolis was first and foremost a city of civil servants, full of institutions like the fire brigades. With no political will, afflicted by unrest and internecine political struggle to control it, as well as by the pernicious flea, and at a time of drastically unsettled weather, a perfect storm seems to have extinguished Rome’s administrative classes. That is certainly the upshot of visiting the Crypta Balbi museum, close to the Largo Argentina where Julius Caesar met his end.
Excavating an insula
This discreet museum is a shrine for me. Here history was made by archaeologists who gave texture to Rome’s imperial twilight and its aftermath. The museum’s exhibitions date from the city’s bi-millennial celebrations, when the city last invested lavishly in its historical assets. At its heart is a celebrated dig, a vaunting and ambitious project by the sagacious and elfin Daniele Manacorda, then a professor at Siena University. Starting in 1982, Manacorda was already a veteran of many digs in Rome and around the Mediterranean. He had cut his teeth unearthing Roman monuments and houses, but rarely placed them in meaningful context. His dream, which he set before the bold superintendent of Rome antiquities Adriano La Regina, was to excavate an ancient insula – a city block – from the 19th century back to Etruscan times. La Regina encouraged him, and apart from his stirring discoveries, the young Manacorda trained a generation. The teams that dug here included many who went on to be professors in countless fields. All were touched by Manacorda’s vision as well as his kindly intellect.
Gargantuan digs
After more than a decade of gargantuan digs producing warehouses full of finds, it became abundantly clear that the dream was both extraordinarily important and excessive. Important because the wealth of evidence for certain periods was unexpected, excessive because the city did not possess the funds to unearth more than a bite-sized section of the area once associated with the fabled patrician, Balbus.
Lucius Cornelius Balbus was a Spaniard from Cadiz and a prominent member of Emperor Augustus’s inner circle. He acquired land in the Campus Martius to construct a theatre after his patron’s victory over Libya in 19 BC. Finished in 13 BC, it was opened while the Tiber was in flood. Behind the theatre lay a large, rectangular, enclosed building with a semi-circular exedra on its eastern side. Manacorda’s excavations, now splendidly published, discovered Etruscan phases and Republican buildings, as well as the steady evolution of Balbus’s monumental legacy after the great fire of 80 AD.