Broadmoor is often viewed as the dumping ground for some of the country's most notorious criminals, like the Yorkshire Ripper, Peter Sutcliffe. But, as the Today programme's Tom Feilden discovered, the reality of life behind its walls is rather different.
"Broadmoor is a hospital not a prison, and patients - not prisoners - do move on and back out into the community."
I've barely even sat down in his office in the administrative block overlooking Broadmoor before the clinical director, Dr Kevin Murray, launches into what he regards as the single most pernicious myth hanging over the hospital - and a big part of the reason why the West London Mental Health Trust has agreed to let me in to Britain's most notorious high-security facility.
"There is a general perception that people come to Broadmoor and we throw away the key and they're here for ever. That's certainly not the case".
And of course he is right. Although some of the most damaged and dangerous patients may never leave, the average length of stay at Broadmoor is actually just six years.
During that time patients are exposed to an intensive programme of drug, and psychological, therapies. Depending on their response to that treatment a patient might expect to move on to another, medium-secure facility, and ultimately back out into wider society.
In that sense, Broadmoor is just one part of a wider forensic psychiatric care system that aims to identify and treat people suffering from a mental disorder.
Broadmoor's staff treat patients with a range of intensive therapies
But that does not mean security is not taken extremely seriously. For all the talk of hospital and treatments, Broadmoor retains the status of a Category B prison. Just getting in involves a series of biometric tests, airport style security scans and a thorough physical search.
Once inside, movements are strictly regulated from a central control room. At any one time, the head of security Mike Humphrey claims, his staff know where every patient is, and access around the hospital grounds is controlled via a series of electronic gates.
As if to make the point the deputy director of nursing Jimmy Noak and I have to wait to be buzzed through Broadmoor's real perimeter: a higher, and much more technologically-secure, steel fence that runs inside the hospital's familiar redbrick walls.
My first impression of the scattered mix of Victorian wards and more modern additional buildings is of a small provincial hospital or university campus.
But this is not the way the typical patient - who may have been transferred from a medium-secure unit, or more likely prison - arrives at Broadmoor.
"Admissions can be very difficult," according to Jimmy Noak. "Patients can be very psychotic, very disorientated and thought disturbed on arrival.
"They may be very aggressive and violent, and if you think about it from their point of view, if you're not in a stable state of mind and you think everyone's out to get you it can be very frightening."
A comprehensive assessment of the patient's history, their illness and treatment requirements, lasting up to three months is undertaken before a patient is ready to move on, usually to a high dependency ward in the main body of the hospital. Here the real work on treatment can begin.
Although each case is different, consultant forensic psychologist Dr Shaun Battacherjee says, patients can be broadly divided into two categories: those suffering from mental illnesses like schizophrenia; and those suffering from personality disorders.
High security: But the average stay at the hospital is just six years
Treatment regimes usually involve a combination of powerful anti-psychotic drugs and intensive psychological therapies.
A key element, and a word you hear a lot in Broadmoor, is "insight". Getting patients to acknowledge they are suffering from a mental disorder, and to understand its role in their offending.
"The trick in deciding what treatments are going to be appropriate for a patient is to fully understand their illness," Dr Battacherjee explains. "Allowing the patient to have greater insight and control over his behaviour."
Just about the last thing I expected when I arrived at Broadmoor was to find patients, including paranoid schizophrenics, playing a computer game in which everyone is out to get them.
The Secret Agent programme has been developed by Dr Susan Young and presents players with a series of risk-based and moral decisions.
It helps researchers like Dr Young to assess patients on a variety of scales including empathy, altruism and moral reasoning, and can be used to demonstrate to those patients how their decision making may differ from the average man on the street.
"The game is a great tool that tells us where the patient is and informs us about what kinds of interventions might be appropriate," she says.
"But it's also very illuminating for them because we can sit down and say look this is how you scored, this is what you were doing. Do you want to do something about that? We can help you do something about that."
Research into the basis of mental disorder is an important component of the work that goes on at Broadmoor. Using Magnetic Resonance Imaging, or MRI, scans of the brain Dr Migendra Das is trying to understand why a small minority of people suffering from an acute mental illness resort to violence.
The study, carried out at the neural imaging unit of the Maudsley Hospital in south London, revealed significant differences in the structure of the brains of patients at Broadmoor hospital, and interestingly, a marked difference in fear responses and inhibition processing between schizophrenic patients and those with a personality disorder.
While the schizophrenics in the study were overly-stimulated by the prospect of a mild electric shock - none were actually delivered during the study - the brains of patients with personality disorders showed a much more muted emotional response.
Activities like art are not part of the therapy but are seen as part of the cure
"This kind of imaging study can be important in helping to develop useful diagnostic tools," Dr Das suggests "and broaden our understanding of the bio-chemistry of mental disorder".
Inevitably patients need some respite from the emotional intensity of the psychological therapies they go through. Confronting, and coming to terms with what they may have done - even while in the grip of severe mental illness - takes its toll.
Broadmoor offers a range of extra-curricular activities in its well equipped carpentry, and arts and crafts workshops, music studios and extensive kitchen garden. Although it is not part of the treatment Tony Roche, who runs the music school, says it is definitely part of the cure.
"The treatments are very tough, and emotionally draining. Patients need some down-time, some space to get away, and we can offer them skills and opportunities that may help boost their confidence, and that they can use to reintegrate back into society."
It was at this point that a nagging concern about the extraordinary level of effort and investment being channelled into the patients at Broadmoor bubbled to the surface.
Many of these men - they are all men at Broadmoor - had committed the worst crimes of violence imaginable. What about the victims of those crimes? What about their families?
"It's not fair, but what is the alternative? If these people committed crimes because they were suffering from an acute mental illness then they should be in hospital," Jimmy Noak told me.
"In any civilised society you should be treating people who have a serious mental illness in a hospital."
This page is best viewed in an up-to-date web browser with style sheets (CSS) enabled. While you will be able to view the content of this page in your current browser, you will not be able to get the full visual experience. Please consider upgrading your browser software or enabling style sheets (CSS) if you are able to do so.