A prison at the centre of the jails safety crisis is overcrowded, violent and run-down, a report has found.
HMP Pentonville came under the spotlight last year after it was the scene of an alleged murder, followed weeks later by the escape of two inmates.
A report from HM Inspectorate of Prisons said the north London establishment had made some progress but was still not safe enough.
In the six months before the visit in January, there had been 196 assaults on staff and prisoners. Many of the incidents were serious, and some involved weapons, the report said.
Gang behaviour at the jail is "pervasive", while drug availability was high, the assessment found.
It also noted that there had been five self-inflicted deaths since the previous inspection, while around one in five prisoners were on anti-psychotic medication.
Chief inspector of prisons Peter Clarke said: "HMP Pentonville remains a large, overcrowded Victorian local prison serving courts in North London, holding over 1,200 adult and young adult men.
"The population is complex and demanding."
The report said the escape of two prisoners in November "had exposed some weaknesses in physical security" and prompted investment in anti-drone technology, new security netting, patrol dogs and a "long overdue" programme to install replacement cell windows.
Inspectors also welcomed measures to address levels of disorder and limit the supply of drugs, as well as improvements in staff-prisoner relationships.
Mr Clarke said: "It is clear that Pentonville remains an immensely challenging prison, and that outcomes for prisoners remain, in many respects, not good enough.
"However, we were encouraged to see at this inspection a tangible sense of purpose and optimism among the governor and his senior management team, which were having a galvanising effect on the staff group as a whole."
It is the first prison inspection report published since David Lidington was appointed Justice Secretary last week.
Frances Crook, chief executive of the Howard League for Penal Reform, said: "One of the first documents to land on the desk of the incoming Secretary of State for Justice is a disappointing report on Pentonville prison, as was the case when his predecessor-but-one, Michael Gove, assumed the position less than two years ago.
"That so little has changed in that time only serves to illustrate the scale of the challenge, and the need for urgency to resolve the many problems in our failing prison system."
Michael Spurr, chief executive of HM Prison & Probation Service, said: "Pentonville has been through a very challenging period and I'm pleased that the Inspectorate have recognised progress has been made."