the inmate held in solitary confinement for the longest time in u.s. federal prison was thomas silverstein, held in solitary confinement at the adx florence federal penitentiary in colorado. beginning in 1983. silverstein died in late may 2019. the inmate held in solitary confinement for the longest time in the united states is albert woodfox, the last of the angola three, in solitary in louisiana state penitentiary from 1972 to 2016. a may 2013 report on california's pelican bay state prison in "mother jones" magazine also cites one inmate there who "recently marked his 40th year in solitary".