Behind Bars: The World's Toughest Prisons Season 4: Episode Guide & Ratings

New Bilibid Prison is one of the most notorious prisons in the Philippines. Originally designed to hold 1500 offenders, there are currently more than 8000 incarcerated there.

The toughest and most heavily-guarded prison in Croatia. The country’s 500 most dangerous criminals serve their sentences here – and every day the struggle for survival begins anew.

Taichung Men’s Prison is the biggest and toughest in Taiwan, housing some of the country’s most dangerous criminals and operating a system of ‘progressive correctional treatment’.