It was raining heavily on 28 March 2018, as Alessandro Albini’s officers were raking over rough ground on the outskirts of an abandoned building. The police were looking for stashes of drugs or money, because they knew the shack was being used by dealers.

At first glance, this might have seemed an unlikely location for a drugs bust. Porto Recanati is a small seaside town on Italy’s Adriatic coast. It has perpendicular streets with low, pastel-coloured palazzi between palms and maritime pines. It’s all very neat: there are often mini-diggers on the sand, raking the beach flat as if it were a Japanese garden.

One of Albini’s men called him over. “There’s something strange here,” he said. The rain had washed away the loose soil and what looked like a golf ball was sticking out of the ground. Albini’s colleague took a cloth and wiped away the mud so that he could see the thick bone of what appeared to be a femur.

Forensic experts were called in, and for two weeks Albini, the town’s vice questore (the deputy chief constable), oversaw the sifting of 15 cubic metres of ground, which contained a lot of buried garbage and animal bones, but also other remains that seemed human.

The abandoned building was five minutes inland from the sea, close to the town’s tiny stadium with its single west stand. But it was only a field away from what is possibly the most fascinating and perplexing building in Italy: Hotel House, a semi-derelict tower block that has become synonymous, in the Italian imagination, with drug dealing, prostitution and clandestine migrants.

Given that reputation, there was press speculation that this might be a mass burial site. Every day local, then national, journalists came to lean over the red-and-white tape to shout questions to the forensics crew.

Hotel House is shaped like a Y, with three red-coloured wings, each 17 stories high and covered by the rusting sequins of satellite dishes. There are 480 apartments, but nobody knows how many people live here. In the summer, when large numbers of Bangladeshi and Senegalese people come to the area to work as beach vendors, the number probably surpasses 3,000. There are only a handful of Italians still living in the block. All eight of its lifts are broken, there is no piped drinking water, the sewage is backing up and there are holes in the walls and floors on every level.

Hotel House has been compared to Scampia – the famous Naples estate featured in the film Gomorrah – and the former Olympic village in Turin: high-concept architectural projects that have, over time, become dystopian citadels for drug dealers and an Italian and immigrant underclass. These are places where honest destitution mixes with criminal wealth, and where the Italian state often appears to have lost control completely.

For almost a century, Italy was one of Europe’s largest sources of emigrants. But by the early 1990s, immigration to Italy had accelerated rapidly, and some places with high immigrant populations developed serious problems with crime – which in turn provoked outrage among many Italians. Matteo Salvini’s far-right Lega party swept to power this spring by exploiting anti-immigrant sentiment, even posing for a photo opportunity a few years ago at Hotel House.

Italy’s various law enforcement agencies do attempt to police Hotel House, but with so many flats and people, plus multiple stairwells and underground garages, finding evidence of criminal activity is almost impossible. “By the time we get to the top of one stairwell,” one officer told me, “the stash has been moved to another wing. They’re very sly.”

There are occasional busts, after which photos of clingfilmed bricks of hash or torpedo-shaped wraps of heroin or cocaine will be proudly shown off. One recent investigation discovered that about €450,000 was being transferred to Bangladesh, Afghanistan and Pakistan every month from a wire service on the ground floor of Hotel House. Often there were multiple transfers to the same person in one day, indicating that it was a restocking exercise. The drug trade inside Hotel House is estimated to be worth between €5m and €10m a year – not huge figures, but in a building in which poverty and degradation are everywhere, still pretty astonishing.

Given the building’s reputation, few were surprised by the grim discovery of human remains nearby. But Hotel House isn’t simply the key to understanding a murder. It’s also a way to glimpse how parts of Italy have responded to immigration. Thirty years ago, this rural region half-way down Italy’s east coast, Le Marche, was a homogenous society. It is now 6% non-Italian, and in little Porto Recanati, the figure is 23%. Hotel House, in many ways, reveals how bewildering these changes have been – not just for Italian society, but for those hoping to become a part of it.

Almost every week there’s a major incident at Hotel House. Recently these have included a suicide attempt, a Moroccan man beaten into a coma on a Saturday night, a fire, a police bust that turned up 28,000 items of counterfeit clothing, and another that found 120g of cocaine. The discovery of human remains so close to the building was just the latest in a long line of bad news.

Despite constant horror stories in the press, Hotel House doesn’t feel particularly edgy at first. As you approach the block from the sea, you walk through a shady boulevard of mature lime trees, and sunflowers poke their manes above a wheatfield. Next to the building is a large car park and car cemetery, containing dozens of dented, unmarked white vans. There is a constant stream of cyclists and pedestrians walking to and from town, and as you get closer you hear screams of laughter from children playing.

Beyond the pedestrian barriers, Pakistani men sit on the concrete benches, and around the corner North Africans occupy plastic chairs. One time when I visited, a white woman with a grey crew-cut was shouting amiably at Tunisian labourers working to fix some pipes in a trench. The air all around smells of grey water and rotting food.

The porter’s lodge has a mirror window. The porters aren’t official, because the building has been in the hands of a judicially appointed administrator since 2015. But Luca, Ibrahim, Abid and Moustaffa sit in their office gruffly watching the comings and goings. Their powers are limited, but not insignificant: they liaise with the press and police, and hold various keys.

All around the ground floor are notices in Urdu, Punjabi, Bengali and Arabic: appeals to raise money to repatriate a corpse, or posters asking residents to fork out for repairs. You can glimpse faded grandeur in the beige marble flooring, which is now covered by cigarette butts, cotton buds and empty bottles.

Survival means minding your own business. Enzo, a Tuscan glass-blower who has lived here since 2001, says: “I don’t look, but just pass by.” Many apartment doors are posted with repossession orders, but others have been prettified with stencils or shells and pieces of driftwood. Most of the landings are full of rubbish: dirty mattresses, rusting fridges, ripped bin liners, plastic toys. At the end of each corridor is a view that gets more spectacular the higher you go.

The Adriatic seen from Hotel House. Photograph: Supplied by Tobias Jones

You know what floor you’re on by the numbers spray-painted on (or scratched into) the walls. There’s a lot of graffiti in English: “fuck this is not the truth”, and “I’m alone I’m fine”. There are philosophical asides in Italian, too: “The people who ruined this country wear ties, not tattoos.”

It’s estimated that there are about 50 full-time drug dealers here – buying, cutting, bagging and slinging. Not everyone on the higher floors is a criminal, but it is like an inverse of Dante’s layers of hell: the higher you go, the darker it feels. Many doors have been damaged in previous busts. There are rugby-ball-sized holes in the walls and floors. You can see those white vans far below now, nothing more than maggots. Even here there are toddlers playing catch, laughing and smiling next to a window hanging on by a single hinge.

Franca, the woman with the grey crew-cut, lives on the 13th floor. She is fired up about the “potential” of this place. One floor above her is Otello, an ex-missionary who now repairs electronic goods for residents and gives his homemade jams to kids who help him get his shopping up all those stairs. Many of the flats are immaculate inside: the public space is horrific, but the private is spotless.

On the top floor, you’re almost 100 metres up, the sea breeze blasting through the empty window frames. From here the sea is two-tone: turquoise and almost purple. Next to the lift, a fuse box hangs open, with hundreds of coloured wires spilling out. You’re more conscious, at this height, that the rusting fire escape that serves the entire east wing has been locked off.

It was never supposed to be like this. Hotel House was given its odd name because its architect, Antonio Sperimenti, was offering purchasers the chance to “live between domestic walls with all the services of a grand hotel”. Inaugurated in 1968, the building made you feel like you were in the Hilton: the reception featured a bronze lift plate, lush red carpets and large house plants. The ground floors were filled with fashion and food outlets, and even a Bulgari shop.

The flats were all identical – 60 sq metres inside, with 18 sq metres of balcony. The ones looking out to sea were the most expensive, but the other way wasn’t bad either. To the west you could enjoy sunsets over the hills and, in the distance, the Sibillini mountains.

The design was inspired by the Swiss architect Le Corbusier, and by the French utopianist Charles Fourier’s notion of a phalanstère, an ideal residence for a community of 1,600 people. It was deliberately monumental, dwarfing the more usual two- and three-storey apartment buildings in town.

Italians from big, land-locked cities such as Milan, Bergamo and Bologna (a few hundred kilometres away) snapped up the flats as second homes by the sea. Luca Davide, who moved here in 1977, and is now one of the porters, told me: “We felt like we were the sons of Agnelli [one of Italy’s wealthiest families]”. A flat back then cost 12m lire (around £7,000). “If you lived in this building”, Luca said wistfully, “it was as if someone had written you a reference. You were respectable.”

The lure of the seaside wasn’t just sunbathing and seafood. There were religious and literary attractions to Porto Recanati: the famous Loreto shrine is a short drive inland, and one of Italy’s most famous poets, Giacomo Leopardi, was born here.

Outside the main cities of Pescara and Ancona, much of Le Marche’s coast used to be bare marshland with long pine forests. But in the 1970s many new hotels and high-rises were built. Long, sandy beaches were privatised, offering grid-formation deckchairs to sunbathers. New roads were built, including a bypass alongside the railway. But Hotel House was just the wrong side of both. As the town modernised, the building began to seem dated, and stuck on the wrong side of the tracks.

When Italy went through a major recession in the late 1980s and early 90s, many families with second homes had to sell up. Suddenly there was a glut of Hotel House flats on the market, and local businessmen snapped them up. One man from the next village came to own 30 of them. Many others were repossessed by banks.

Residents started to fall behind on their contributions to the spese condominiali – the shared expenses of the block. Some slum landlords charged the communal costs to their tenants, but never passed them on.

With increasing numbers of flats in absentee hands, residents’ meetings were no longer well-attended. Italian law requires a majority of owners’ votes for a building’s budget to be formally approved, and if it isn’t approved, everyone is exempt from paying the communal fees. Soon the maintenance costs could no longer be met.

By the 2000s, many of the original owners of Hotel House’s flats had died, and their descendents usually tried to sell up. You could still, in 2000, get roughly €60,000 for a flat there. Enzo, the glass-blower, bought his in 2001. If owners couldn’t sell, they rented them out cheaply, which made the place more of a magnet for the poor. The majority of newcomers were Senegalese, Pakistani, Bangladeshi and Tunisian. Almost all looked for and found work: the men in Ancona’s shipyards or as builders, and the women as carers, nurses, waitresses and cleaners.

A mosque opened on the ground floor and appointed an imam who was also a great baker. Nigerian Christians worshipped in the boiler room. A halal butcher opened. Soon there were so many Muslims that the Italian bar-owner would shut for Ramadan, since it was pointless to stay open. Cheap rent wasn’t the only attraction for migrant workers: in high season, the beaches were full of holidaymakers keen to buy sunglasses, sarongs and bangles. Thus every summer the immigrant population of Hotel House increased exponentially as incoming workers kipped on friends’ or gangmasters’ floors.

In 2008, all of the lifts were still working. But then recession hit again, and apartment prices fell further. There was now a noticeable criminal element in the block, pimping and drug dealing. Two of the lifts stopped working, and there was no money to repair them. Mismanagement of communal maintenance funds had created a debt of hundreds of thousands of euros.

Rubbish blocking the broken lifts in the hallway of Hotel House. Photograph: Supplied by Tobias Jones

There was also a logistical difficulty: because all the flats were in private hands, Hotel House was unlike other notorious estates across Europe, many of which were run by the state. The regional government couldn’t intervene and invest in improvements without appearing to subsidise slum landlords and banks with public money.

As debts to utility companies increased, services were slowly cut off: one by one, the lifts stopped working and weren’t repaired. The water supply was switched off in 2008. An illegal well was sunk outside, which has served all the flats ever since. The water is undrinkable, but can be used for washing. Many doubtless use it to cook, as getting gallons of water up multiple floors is too much effort. Drinking water comes from a truck in the car park, at which a constant stream of people queue up to refill plastic demijohns and jerrycans.

The cost of not having functioning lifts is almost worse than the lack of water. An old man died last winter because he wanted to catch his breath one night before tackling the steps. He sat on the bench and fell asleep, where he died of exposure. Many elderly residents are prisoners in their own homes, enjoying the sensational views of the sea, but never able to go there again. Lamine Cisse, a Senegalese porter, fell eight floors to his death three years ago, when he stepped into the shaft to try and fix a lift. His widow and child went back to Senegal. Some people have told me that he was an honest, hardworking man who was trying to tackle drug dealing, and that his death was suspicious. He would never have been so stupid, they say, as to attempt to fix a lift inside an eight-storey drop.

Today it’s almost inconceivable that a local would buy a flat here, but there’s still a regular turnover of immigrants attracted by the dirt-cheap property and the presence of so many compatriots. It’s a place of strange speculation: when things are this cheap, both the poor and those who exploit them see an opportunity. A flat now costs only €6,000, and if you buy-to-let without worrying about paying for repairs or safety equipment, your investment could be paid off in 18 months. And for as long as everything is in private hands, the state is unwilling or unable to intervene.

Elisabetta Micciarelli is the headmistress of a primary school in Ancona, 30km north of Porto Recanati. She’s in her 50s, lithe and grey-haired, energetic and idealistic. “Integration”, she says, “occurs because of the host, not the guest. If your child has a birthday party and you don’t invite the foreign child in his class, it’s not going to happen.”

Silvia Mainardi, one of the teachers, points out various students. “That lad,” she says, pointing out a cheery seven-year-old running around the corridors, “was found wandering alone along the Greek-Albanian border. He was adopted by an Italian family. That boy arrived here from Libya on a dinghy with his father.”

There are so many immigrant children in the school that it has deliberately become a holistic place of healing and recreation. Micciarelli and her staff work almost as much with the families as with their children, and the school has a psychologist available to parents. “We’re often the only place where they are listened to,” Micciarelli says. The school has founded a charity, Si Può Fare (“We can do it”) and runs courses for mothers, as well as free after-school courses in music, theatre, sports and even sailing for the poorest children.

Every few weeks a new student arrives, usually frightened and traumatised, not speaking Italian, often not even knowing its alphabet. In 2005, four siblings, the Mossamets, joined the school. Asik, Cameyi, Sajid and Jsan were from Bangladesh, and had come with their mother to be with their father, Ibrahim, who had been working in a factory in Camerano, just south of Ancona, for years. Only the oldest child had stayed in Bangladesh.

Their difficulties were huge. The mother was illiterate, and Sajid was deaf-mute, and had never had any education. Their father seemed to have fallen out with the local Bangladeshi community, some said because he had been drinking too much. Even by immigrant standards, they were isolated and facing immense challenges.

But Cameyi, who was 10, was bright and vivacious. Because she was put in a class of younger children, she was looked up to by her peers. She was like most girls her age: singing pop songs, window-shopping, going for a passeggiata – a stroll – along the city’s boulevards. Her Italian quickly improved, and she was soon like a second mother in the family, translating for everyone.

To say the school went the extra mile is an understatement. Mainardi used her knowledge of sign language to communicate with Sajid and translate the Qur’an for him. She often invited the siblings to dinner in order, as she says, to “raise them out of poverty”. Mainardi took Cameyi and her siblings to doctors’ appointments. They regularly stayed overnight in her flat, squeezing in with her own children.

The family had been in Italy for five years when things started to go wrong. Cameyi’s father was diagnosed with lung cancer. He lost his job, and by late 2009 had fallen behind on rent payments. One day Cameyi was asked into the headmistress’s office after school. There were two social workers there, who said she couldn’t go home. Her family’s flat had been repossessed. All her clothes and makeup, her trinkets and teddy bears were gone.

Social services had arranged a room for Cameyi, her mother and for her two younger siblings, in a grotty hotel near the station. Her older brother Asik and her father – who was undergoing chemotherapy that day and, according to the teachers, “vomiting every three paces” – would be left on the streets.

Again the teachers pulled out all the stops. For a month and half they raised enough money to pay for a hotel room so that Ibrahim and Asik could be with their family. “I even told my father’s car mechanic that I needed €50,” Mainardi laughs, “and he just opened his till and took it. People were incredibly generous.”

Mainardi showed me a photo of the new flat that social services eventually found for the family. The walls are so grey and black with mould, but Cameyi is on the sofa, smiling. By then she was 15 and bored with school. The headmistress says that Cameyi seemed to have pulsioni, a word that implies both “instincts” and “sex drive”.

“I had the idea that she was older than her age,” she remembers. “She had a longing for love, she was in love with love. She was putting on makeup, hoping to be on show, longing to redeem herself.”

Cameyi was also finding her family claustrophobic. She told the teachers she wanted to come to all the after-school courses, but that she wasn’t allowed. “I went to pick her up for school one day”, recalls Mainardi, “and she was sitting there with her two younger siblings looking extremely grumpy.” Like most teenagers, Cameyi must have often resented her relatives, feeling ashamed or embarrassed by people who seemed to her disabled, illiterate, ill and unemployed.

Then, early one morning in May 2010, says Micciarelli, a desperate Ibrahim came into her office and said that Cameyi hadn’t been home all night. Micciarelli accompanied him to the police station and reported the young girl missing.

Many people feel the investigation wasn’t anything like as thorough as it should have been. “There were prejudices,” said one person, who didn’t want to be named. “It was as if she was some troietta [‘little tart’].” There was nothing like the outcry and publicity there would have been if the missing girl had been a white Italian. One investigative lead (which the teachers, given the family’s struggles, found ridiculous) was that the family had organised Cameyi’s abduction and repatriation because she was becoming “too emancipated”.

Micciarelli and Mainardi went through Cameyi’s schoolbooks and found a diary. In it were all sorts of love hearts and ti amo (“I love you”) scrawlings. The name written in the teenager’s diary, the seeming object of her infatuation, was Monir Kazi.

The investigation picked up speed. Some claimed to have seen Cameyi at the railway station catching a train south towards Porto Recanati. Kazi was 20, five years older than her, and lived in an eighth-floor flat at Hotel House with four others. He had met Cameyi in Ancona, where his sister lived. A photograph of the two kissing had been shared on Myspace.

When police went through Hotel House’s CCTV (which has since stopped working), Cameyi was seen entering alone. “She didn’t have the maturity to recognise the danger of a building that would repel you or me,” says Mainardi. “Her problem was her innocence, not her so-called emancipation.”

Investigators obtained a search warrant for Kazi’s flat. His pillow had blood on it, but when tested it didn’t show a match for Cameyi’s. Kazi had gone to hospital for hours on the day she went missing, complaining of stomach cramps. Even more suspicious was his decision suddenly to up sticks: he left Italy to go to Greece. In July of that year, Cameyi’s father died.

Cameyi Mossamet. Photograph: Porto/Twitter

Police couldn’t begin extradition proceedings without evidence, and they had none. Kazi eventually returned to Italy but, in 2011, was expelled from the country. The investigation into the missing 15-year-old petered out, and many people felt there was a lack of urgency because the missing person lacked well-connected Italian relatives. “Over the years,” says Silvia Mainardi, “no one spoke about this case in the city: there were no processions, appeals, nothing to move public opinion.”

When you ask Micciarelli, the headmistress, how Ancona has changed after 30 years of immigration, she says something unexpected: “It hasn’t changed at all. There are just two Anconas now, because all the foreigners are concentrated in certain areas.”

Mainardi remained close to Cameyi’s family, who were convinced Cameyi had left home for a better life. Mainardi even became so fascinated by the idealism and dysfunctionality of the immigration system – “something had so clearly gone wrong here” – that she became an external student of the subject at Bologna University.

At the end of June this year, three months after the femur was found, confirmation arrived that the human remains from the drug dealer’s abandoned building were those of Cameyi. It was, by then, over eight years since her disappearance. Investigators always talk about speed and momentum, but a few years, in the chaotic life of Hotel House, is like a century. All trace of Kazi is gone, and investigators admit they don’t know where he is.

“I always had the sense that everything led to Hotel House,” says Mainardi. But this new proof was “a chilling change of perspective”. She is a cheerful woman by habit, but is angered by the lack of dignity afforded to Cameyi even in death: “That ditch was a general dumping ground for rubbish. That’s what really hurts.”

At Hotel House, residents are weary of all the bad press because, they say, outsiders don’t see what really goes on. Most of the fights aren’t examples of gang warfare but just arguments between cricketers from Asia and footballers from Africa about who can play on the makeshift concrete pitch. Punch-ups that have been written up as drug dealers’ turf wars, they’ll tell you, were really over a bike or a woman – just as happens everywhere when men have drunk too much.

And it’s true that the longer you’re there, the serenity emerges as much as the darkness. The building has been a marginalised community for so long that there are now second-generation “hotel-dwellers”: 404 minors live in the building. They make the place noisy and playful. As I watched a game of five-a-side with Franca, she named them all and their nationalities: Macedonian, Pakistani, Bangladeshi, Algerian … but they were all screaming at each other in slangy Italian. Without even thinking about it, they are linguistic natives.

One of the most interesting aspects of the building is the hopefulness of the Italian residents. They represent about half a percent of Hotel House’s population. They have long given up on the idea of getting back what their flats were once worth – but that, you sense, isn’t the only reason they haven’t moved out.

Luca Davide, the porter, told me why he stays on: “Here there’s goodness, and we’ve got to help it emerge, to make the world understand that 30 ethnicities can coexist peacefully.” Although realistic about the building’s problems, Davide is fond of the ethnic diversity. “We could become a beacon of integration. We could have people envy what we’ve created.” The struggles of his neighbours, he says, are his own: “Our interests are complementary, they overlap.”

On the 11th floor there’s a retired air force colonel, Alfredo La Rosa, who was born in Libya. The place reminds him of housing estates where he grew up, where people survived with barely anything. “Hotel House”, he told Internazionale magazine recently, “speaks of our future, of the multiethnic society that is coming. This building could be a great opportunity to experiment with forms of coexistence.”

Another draw for the remaining Italians is that they, knowing how to make things happen, can improve peoples’ lives very simply. Franca got the mayor to turn a couple of streetlamps around to act as floodlights for the one grass pitch. Enzo bought the chalk for the lines. Franca goes and knocks on doors until 200 people have stumped up €40 each to repair and replace the sewers.

When those Italians talk about integration, they sound plaintive, not xenophobic. “For true integration,” Enzo the glass-blower says, “you have to understand how things work here, you have to be able to adapt in order not to be marginalised.” You get the sense that the Italians now see themselves as a tiny, often ignored, minority.

Every time you go there, you’re also struck by the variety: a Tunisian teenager in a catalogue-clean flat studying fashion, hoping to get to the Accademia in Milan; an Italian doctor who holds a surgery on the eighth floor; the Pakistani cricketer who hopes to play for the Italian national team. There’s both integration and isolation. The most isolated, you sense, are the wives who you only see once a week when they catch the Thursday bus to market.

Nobody denies Hotel House’s problems. Police know that drug users are still coming from 400km away to score wholesale. But the business is still tiny compared to, say, Naples, Rome or Milan. National law enforcement agencies have bigger fish to fry than Hotel House. And so it lingers on, in its uniquely extra-statal, self-regulating way.

Every initiative seems to bounce off it. The mayor of Porto Recanati ordered its complete evacuation by December last year if safety measures were not put in place, but that deadline passed and people stayed. The regional government has lent the building’s administrator €100,000 to renovate the external areas and begin safety work, but the loan has irritated law-abiding locals who say it’s a state bailout that rewards illegality. The doomsday scenario – in which a fire engulfs the whole building – seems worryingly imaginable.

And yet it is a home to thousands. There are 30 legitimate businesses. Qui sto bene, almost everyone says: “I’m good here.” Many say benissimo. One Senegalese man says to me in thumpy Italian: “It’s not so different to Senegal: the beach, the rubbish, the struggle.” Every time you go, you meet someone new, but often, when you ask after someone you met last time, you’re told they’ve moved on. There’s little permanence in migrancy.

Given that the police don’t even know precisely who is living at Hotel House, it seems far-fetched that they’ll ever find someone who left here seven years ago. Nobody knows where Monir Kazi is. A missing person has been found, but the man who knows most about her death will probably never be seen again.

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