The Most Notorious Prisons in US and UK History, Ranked

Known as the "Alcatraz of the Rockies," this ultra-secure federal Supermax facility in Fremont County, Colorado, holds America's most dangerous domestic and international convicts. Inmates spend up to 23 hours a day in soundproofed, poured-concrete cells under near-total isolation.

Originally built as a house of correction in 1594, this Category A high-security facility in West Yorkshire is nicknamed the "Monster Mansion." It houses the highest concentration of Britain's most dangerous life-sentence murderers and high-risk sex offenders.

Perched on a rocky outcrop surrounded by the freezing, treacherous currents of San Francisco Bay, "The Rock" operated as a maximum-security federal penitentiary from 1934 to 1963. Housing infamous figures like Al Capone and Robert Stroud, the island fortress was deemed inescapable.

Operational since 1991 in southeast London, this Category A men's prison became known as "Britain's Guantanamo" for its ultra-secure High Security Unit. HMP Belmarsh regularly holds high-risk terrorism suspects, maximum-security convicts, and high-profile figures awaiting extradition.

Spanning 18,000 acres on the site of former slave plantations bordered by the Mississippi River, Louisiana State Penitentiary—known as "Angola"—is the largest maximum-security prison in the US. Decades of violence in the 20th century earned it a reputation as America's bloodiest prison.

Founded by William the Conqueror in 1066, this historic royal fortress on the River Thames served for centuries as Britain's most dreaded state prison. Brought through the infamous Traitors' Gate, high-profile royals and political prisoners—including Anne Boleyn—met their fate here.

Opened in 1852 overlooking northern San Francisco Bay, California's oldest correctional facility is historically notorious for severe overcrowding, intense yard gang violence, and housing the largest death row population in the United States inside its massive cellblocks.

Designed with an iconic Victorian ventilation tower and opened in 1868, HMP Strangeways (now HM Prison Manchester) is a Category A facility famous for its brutal 25-day rooftop siege in April 1990—a devastating uprising that remains the longest prison riot in British history.

Occupying a 413-acre island in New York City's East River since 1932, Rikers Island is one of the world's largest jail complexes. For decades, the facility has been notorious for severe gang violence, harsh solitary confinement conditions, and holding high-profile pre-trial detainees.

Built in 1809 high on the fog-shrouded Devonshire moors to hold Napoleonic War prisoners, HMP Dartmoor later became one of Britain's most feared convict prisons. Surrounded by miles of treacherous bogland, the isolated granite fortress held some of the UK's most hardened criminals.