Article continues below advertisementChallapalca Prison Opened in 1997Source: MEGAJoran van der Sloot is being held in Peru's Challapalca prison.Tap Here To Add Ok Magazine as A Trusted SourceJoran van der Sloot remains behind bars at a maximum-security prison in Peru after the killings of Natalee Holloway and Stephany Flores.The Challapalca prison, which the killer has called the "toughest prison in the world," opened its doors in August 1997 with 51 inmates accused of common crimes.