Prisoners' safety is being compromised by overcrowding at Scotland's largest jail, the chief inspectors of prisons has warned.
Barlinnie's prison population climbed by 150 in the past year
Dr Andrew McLellan said conditions at Barlinnie Prison in Glasgow were deteriorating, with its population rising by 150 in the last 12 months.
Relations between staff and prisoners were said to have suffered.
But he stressed that it was an "encouraging" report despite the strain created by a rising population.
Dr McLellan said the relationship between prisoners and staff, as well as inmates' access to "useful" activities, had been affected.
"Since last year's inspection, when overcrowding dominated nearly every conversation about the prison, the problem has got worse," he said.
"Staff numbers do not rise to deal with overcrowding, so the amount of time which prison staff can spend with prisoners - a key matter in maintaining good relationships and providing opportunities for reducing reoffending - is increasingly restricted.
"Very importantly, safety may be more at risk when a prison is so very much overcrowded. How can there be the time to make sure the most vulnerable prisoners are identified when they enter the prison, when there are over 1,200 admissions to Barlinnie every month?"
The chief inspector said it was not a foregone conclusion that the prison could function properly if prisoner numbers continued to rise.
The inspection in April found that prisoners, particularly those on remand, were forced to spend "long hours locked up in their cells".
It also described holding cubicles that prisoners were kept in upon arrival as "essentially cupboards with a bench seat".
The cubicles were "still oppressive" and food served, although "less cold", remained of poor quality.
Dr McLellan said it was "a matter of note" that the prison functioned at all in sych circumstances.
However, he added the investigation showed Barlinnie was "not merely functioning, but progressing".
He welcomed steps taken to end the controversy surrounding slopping out and hoped for an end to the "degrading practice" across the prison estate.
Dr McLellan said the prison was also becoming more organised in its approach to administering methadone and that levels of violence had reduced "considerably".
He said it was "too early to make detailed comment" on the service provided by the troubled prisoner escort firm Reliance.
"Prisoners spoken to had no complaints and a number spoke positively about the attitude of and treatment from the escort staff," he said.
"Overall, this is an encouraging report given the strains being placed on the prison by the high levels of overcrowding."