A look inside the notorious Madagascan prison, where inmates endure overpopulation, malnutrition, and a potentially deadly rodent infestation.

This is the prison city of San Pedro in La Paz, Bolivia, where the inmates rule and anarchy prevails. Only the strongest survive this lawless place and they rule over the weak, demanding protection money.

Exploring the Dallas County Jail in Texas, which has a population larger than many cities and towns, varying from small-time criminals to serial killers.

Crime journalist Paul Connolly goes to the world's toughest prisons to experience the harsh conditions, the claustrophobia of the overcrowded cells and the severe discipline.

Crime journalist Paul Connolly goes to the world's toughest prisons to experience the harsh conditions, the claustrophobia of the overcrowded cells and the severe discipline.

Exploring some of the toughest prisons around the globe.

Exploring some of the toughest prisons around the globe.

An unflinching look inside the world's toughest prisons: the Carcel Distrital in Bogotá, Colombia.

Exploring some of the toughest prisons around the globe.

Crime journalist Paul Connolly is on a mission to experience life as an inmate in El Hongo prison, one of Mexico's toughest maximum security jails where no one has ever escaped.

Exploring some of the toughest prisons around the globe.