There are several prisons around the world that are known for their harsh conditions and are considered among the worst in the world. Here are some of them:

• Gitarama Prison, Rwanda: This is the most crowded prison in the world, with over 7,000 prisoners in a facility that was built to hold only 400.
• ADX Florence, Colorado, USA: This is a supermax prison, one level higher than maximum security, and is home to some of the most dangerous criminals in the US.
• Black Dolphin Prison, Russia: This prison is known for its brutal and rough conditions and houses the countrys most hardened and dangerous criminals, including pedophiles, cannibals, and terrorists.
• Kamiti Maximum Security Prison, Nairobi, Kenya: This prison is known for its overcrowding, lack of proper medical care, and severe risk of violence.
• Melrose Maximum Security Prison, Mauritius: This prison is known for its extreme punishment for even the smallest infraction.
• Manila City Jail, Philippines: This is one of the worlds most overcrowded prisons, and inmates scrounge in the trash to pay their own way.
• Nuuk Maximum Security Prison, Greenland: This prison houses extremely dangerous prisoners, many of whom grew up alongside the guards now watching over them.
• Schwalmstadt, Germany: This 12th-century fortress houses some of Germanys worst offenders, many of whom attend intense therapy sessions.
• Penitentiary 17, Moldova: This maximum-security prison houses more than a hundred life-sentence inmates.
• Central Jail of Nicosia, Cyprus: This prison has undergone radical transformation over the years, but it is unclear if the changes are for the better.

It is worth noting that there are likely many other prisons around the world that are equally as bad or worse than those listed here.