Southway Garrison is the military prison that Desmond was incarcerated at. He was incarcerated for desertion according to the paperwork that was stamped upon his release. ("Live Together, Die Alone, Part 1")
The address of the prison is:
- There is a real Army Garrison in Colchester, Essex which is just known as Colchester Garrison, and houses several regiments. The Garrison is near a road in Colchester named "Southway". Part of this facility is the Army's "Military Corrective Training Centre", the last remaining military prison in the UK. It is located on Berechurch Hall Camp on Berechurch Road, Colchester. The next line of the address in this episode is "Halstead", a small town about 10 miles from Colchester - there are no military facilities here. The postcode given is not a real code, but if you take just the start - CO8 - this corresponds to the village of Bures, Essex, also near Colchester.
- The filming location was an actual prison, Halawa Correctional Facility, a medium security and high security prison deep in Halawa Valley in Aiea, HI.