"The English Channel is a mere ditch which will be crossed when we decide to do so." So spoke Napoleon Bonaparte in November 1803 as he stood gazing at the white cliffs of Dover from Boulogne-sur-mer, where his army had set camp for the planned invasion of Britain.

Napoleon's army never crossed the Channel in the end but two centuries later, France's Nord-Pas-de-Calais region continues to funnel many of those who wish to travel to the United Kingdom. Among them, undocumented migrants from Asia, Africa, Europe and the Middle East who desperately try to smuggle across the Channel on trucks at their own peril.

But tight immigration controls mean that migrants who have made it to Calais find themselves marooned in what has effectively become a blind alley.

Kourosh, a 29-year-old computer graduate from the Iranian town of Tabriz has been walking the streets of Calais for 40 days in a worn-out grey pin-striped suit and faded tie in the hope of making it to the UK where he had been wrongly told by people smugglers he would find easy employment in the IT sector.

"My family sold some property to pay for the trip," says Kourosh. "The trip was fraught with danger but the past six weeks in Calais have been unbearable and I'm fast losing all hope after many unsuccessful attempts to get across."

His friend Aref agrees. He says he sold his share in the family brick making business in Lahore, Pakistan, to pay smugglers.

Their days and nights spent sleeping rough in a dirty, cold and damp squat near the harbour have taken their toll as both turn up on a cold January morning at the local hospital looking pale and gaunt and complaining of violent headaches, nausea and chronic diarrhoea.

Dr El Mouden works as a volunteer emergency practitioner to provide free medical examinations and treatment to migrants. He says that despite their youth and general good health, all migrants end up suffering from physical, mental and emotional exhaustion.

"We have noticed an increase in scabies and other skin diseases, which are linked to overcrowded living conditions and poor hygiene and a marked increase in chronic pulmonary infections caused by sleeping rough in a cold and damp environment," he notes.

He adds that migrants also turn up regularly with scrapes, bruises or with sprained or broken limbs sustained when they try to climb on passing trucks or jump from them to escape arrest.

Kourosh and Aref drag themselves out of the clinic with a handful of drugs and disappear to go back to their insalubrious squat. The harsh realities of irregular migration are fast eroding their determination. Like many others, they continue to look for a way forward… or for a way out.

There are only five shower facilities available for a population estimated to be around three hundred. Because of the overwhelming demand, associations like the "Secours Catholique" have put in place a numbered card system to ensure equal access to the facilities. Their volunteers work with a couple of other non-governmental organizations (NGOs) to provide a cold lunch and a hot supper.

It's a sad sight to see migrants gathered on a piece of waste ground at lunchtime, huddled around open fires trying to warm up tins of sardines and loaves of bread. Acrid smoke, tearing eyes and flames lick hands made numb by the cold.

Later that afternoon, a young Iranian man turns up at IOM's office in Calais.

Farid's icy cold hands, blackened and broken nails, tired eyes and pale, unshaven face testify to his ordeal.

With his long curly brown hair, dark grey bomber jacket, baggy brown corduroys and blue trainers, Farid looks like any other youth who walks the streets of Calais.

But unlike the locals, he and other young migrants have been barred from entering local supermarkets where they could, until recently, find comfort, warmth and bright lights to dream of better days to come.

"No one told us how miserable life would be in Calais," says Farid. "I left Tehran in November because my father died and I needed to provide for my old mum and for my sister who is now engaged and wants to get married. I was told everything would be easy, that I would find a good job in the UK. But I was lied to. We were all lied to."

Farid is tired of living like a shadow. With a friend, he has come to talk to Nazénine Lajili, IOM's Migrant Information Specialist in Calais to enquire about the possibility of returning home.

Scalding hot tea is served and slowly Farid opens up to Nazénine. He admits his mother has asked him to return home "because he is wasting his time and making no money in Calais."

But he says he has no passport as smugglers told him to get rid of it when he entered Turkey.

"Does your mother have a photocopy of your passport?" asks Nazénine. "Do you have a telephone number for her?"

He pulls out a ruffled piece of paper from his jacket. Nazénine dials a number and hands over the phone to Farid.

With a sigh of relief, he informs IOM that his mother has a photocopy of his passport, which half an hour later, is faxed to IOM's main partner in Calais, France's Agence Nationale de l'Accueil des Etrangers et des Migrations (ANAEM).

Later in the afternoon, Farid is informed he will be returning home in the next 72 hours on a regular flight from Paris with a Euro 2,000 reintegration grant in his pocket.

He says his dreams have been shattered but at least he has found a dignified way out of this cruel impasse.

"Our aim is to establish a real dialogue with the migrants to find humanitarian solutions to the bitter realities they face day after day as they fail to reach the UK," says IOM's Nazénine. "Establishing trust with the migrants is crucial. This is why I always make myself available when they come for information and counselling. As a rule, they need to talk, to tell of their ordeals. I listen. Then they decide what is best for them."

But not everyone in Calais is willing to give up their dreams of a better life in the UK.

"As long as one person manages to get through, I will continue to hope," says 22-year-old Sahar, one of the few migrant women in Calais.

Her story is one of relentless persistence and stubbornness, some might say of foolishness.

Sahar says she left her home in Asmara, Eritrea, "for a six-month and twenty-two day" odyssey through Sudan and Libya to escape national service.

"The trip across the Sudanese and Libyan deserts lasted 22 days and cost me US$ 1,200. In the desert, a bottle of water costs US$ 10. I simply had no choice. When I finally arrived in Libya, I was broke and had to spend six months saving up before trying to reach the Italian island of Lampedusa."

She says she twice tried to cross the 180 miles of treacherous sea that separate Libya from the Italian island of Lampedusa, each time paying more money to smugglers.

"The first time, the boat I was on overturned off the Libyan coast and thirteen people drowned. I was among the lucky ones. I clung to the hull for several hours before we were rescued by the Libyans," she recalls.

Her second attempt was successful and she finally reached Lampedusa where she filed an asylum claim, which according to her, was rejected.

With no intention of returning to Eritrea, Sahar's only hope is to get to the United Kingdom "where things will be better."

According to IOM's Nazénine Lajili, this perception is widespread.

"Once in northern France, many migrants believe that if they manage to cross the Channel, they will find employment and be able to regularize their status over time. The reality is vastly different as undocumented migrants in the UK have no hope of regularizing their status through an amnesty. They will be vulnerable to abuse and exploitation and will have to live under the constant threat of arrest, detention and forcible return for illegal entry into the UK," she explains.

The unending ordeal in Calais and the near impossibility of fulfilling the dream of getting to the UK could be the straw that breaks the camel's back for other migrants like Farid. For them, the offer of voluntary return is the only ray of hope. But they have to know it is there.

To ensure they have the information they need to make the right decision for them, the Organization has published pamphlets on its French government funded programme which is then distributed among the migrants and partner organizations in Amharic, Arabic, English, Farsi, French, Hindi, Pashto, Somali, Sorani (Kurdish), Tigrignia and Urdu.

It's a tough call to make when so much pain, hardship and money has gone into this journey to the UK and when one is so close to getting there. But turning away from that final hurdle could make the difference between life and death.

For reasons of confidentiality, names in this article have been changed.