Behind Bars: The World's Toughest Prisons - Episode Guide

Old army tents left over from the Korean War house prisoners instead of cells. Will no walls or insulation around them, prisoners endure the unbearable heat of the summer, and the freezing cold of the winter. The Sheriff is a hard man who refuses to spend any more than he has to on his prisoners. Harassment and humiliation is a part of everyday life at Tent City.

Imagine a prison so fierce that guards stay outside for fear of their lives. Inside, the prisoners are in control: murderers, violent offenders, drug bosses. The inmates rule and anarchy prevails. Only the strongest survive this lawless place.

The Dallas County Jail in Texas - a supersized facility with beds for 7,100 inmates. There, inmates brought in for anything from minor crime to serial killing await their court dates. Up to 300 new arrivals come in per day. The biggest threat in the prison? Turf wars. With the surplus of inmates, there is less space to divide up between them, leading to relentless gang warfare.

With a crumbling foundation more than fit for demolition, the conditions in Sofia Central prison is inhospitable for anyone, including criminals. However, with multiple prisoner cells, bunks stacked 3 stories high and horrid isolation cells, prisoners live idly behind bars for 23 hours a day.

The two toughest divisions of the Miami Dade prison complex couldn't be more different. The Miami Dade Boot Camp gives minor offenders a chance to escape the prison through rigorous and unforgiving drills and rules. To many it is a better alternative to rusty iron bars of The Miami-Dade County Jail where murderers, rapists and robbers have their own rules of survival.

The inmates in the Carcel Distrital in Colombia fight many battles: against other prisoners, against the guards and most of all against themselves. It's a battle that most of them lose.

The Carcel Distrital is located in one of the most dangerous quarters of Bogotá. Nearly 950 men and 50 women are imprisoned here. Most are still awaiting their final judgment. Their long wait may last for years: Justice in Columbia is very slow. Frustrating slow. Many frustrated people in one place will always lead to great problems. The 170 staff members have their hands full.

Colony 100 - Ukraine's prison for hardened criminals. All those behind the walls of this Soviet-built prison have either already done time in at least three other Ukrainian jails, or they have committed crimes so heinous that they will never again leave their 100-square-foot-cell in the maximum security wing. The prison is marked by an omnipresent hopelessness.

South Cotabato Jail. One of the most overcrowded prisons in the world. Murderers, rapists, and drug dealers. The guilty and the innocent. All are behind bars together. In a jail designed for 600 prisoners, more than 2000 inmates are crammed into cells the size of shoe boxes. The prison is bursting at the seems, and there is no hope of improvement.

El Hongo is a high-security bunker in Mexico´s desert. With sensors, cameras, mobile phone jammers, this prison is a veritable high-tech fortress. Snipers on fifteen guard towers make sure that nothing can get in or out. El Hongo is deemed perfectly incorruptible in a country where corruption runs through all levels of society like cancer.

Once, inmates in Armenian prisons fell into the hands of the "Thieves in Law," a criminal brotherhood rejecting state authority and living by its own code. They control the prison and control drug trade and smuggling. Nobody knows their leaders, but their power is immense. Armavir prison is the first attempt at limiting their influence.

La Mesa, A Mexican prison just over the US border. The inmates? Drug traffickers, rapists, cartel killers. They have tough times ahead. They hardly get to leave their cells. They sleep, eat, pee, all in a very confined space. Only two square meters for up to eight inmates. La Mesa is ruled with an iron fist.

Exploring Urso-Branco - the white bear - one of the most notorious prisons in Brazil. In the past 20 years more than 100 people have died in riots behind its walls.

Behind the scenes at Colony 8 in Ukraine, one of the toughest and most notorious prisons in the country. It is said that no one has ever escaped from here.

A high-security prison with an area the size of ten football pitches. Surrounded by six-metrehigh walls, and the sea, the facility houses up to 800 criminals.