Locked up for sometimes 23 hours a day mostly with other people it would be hard to find anyone with a good word to say about the space where they spent the majority of their days.

WATCH and LISTEN Listen to the atmosphere inside a Long Lartin Maximum Security Prison (56k) BBC download guide Free Real player

Long Lartin houses offenders who are serving lengthy sentences, who spend much of their day outside the cell and they are all in single units. Consequently I hoped that some of things these men would say about their own cells would be surprising or controversial or enlightening or moving. I wasn’t disappointed.

The main problem, that I alluded to earlier, was that even though none of the people (officers or inmates) are named in the piece it was possible that the members of the public who had been effected by the inmate’s crimes might be able to identify their voices.

This was a major worry for us and the authorities. We are indebted to the staff at Long Lartin and the Home Office for the time and trouble they took in helping us select suitable interviewees.

Once that was completed and I’d met inmates who were keen on talking to me, the project could go ahead.

The building itself is a unique space and in terms of the constant noise and atmosphere, a sound recordists dream. I hope that I’ve captured some sense of that. I suppose if I’m honest the most powerful moment in the making of the program was when I eventually got to interview three prisoners in their respective cells.

Although I’d been in prisons before nothing could prepare me for the feeling when I sat down on their bed and the door was clanged to; I felt very aware that I had the right to leave this space and this seven feet square room would be their home for many, many years to come.

The men talked very generously and movingly about their relationship with this tiny space. So if you’ve ever sat on a London bound train and caught a glimpse of Long Lartin, and wondered what life is like inside; tune into the fourth episode of Sense of Place. I guarantee all your preconceptions will be challenged – mine were.

You can contact the series producer Howard Belgard by e-mailing howard.belgard@bbc.co.uk