The Missouri State Penitentiary was established in 1833 via a bill passed by the state legislature, and the first prisoner was incarcerated in 1835. Inmates constructed the main prison building from rock quarried at the site in 1836. The penitentiary closed on September 15, 2004, and plans are in place to redevelop the site into offices for state agencies and private enterprises. The Missouri State Penitentiary was once considered one of the largest maximum-security penal institutions in the United States. After 550 serious assaults occurred inside the prison in the early 1960s, Time magazine called it "the bloodiest 47 acres in America" (although the walls of the penitentiary only contained 37 acres). The penitentiary had the distinction of housing some very famous individuals: boxing champion Sonny Liston learned to box there under the direction of the prisonchaplain, infamous gangster Charles Arthur "Pretty Boy" Floyd spent time there, and James Earl Ray was an escapee when he shot and killed Dr. Martin Luther King Jr.