Cellblock 2 at the Eastern State Penitentiary in Philadelphia, Pennsylvania. Now a national historic site left in its stark and dilapidated state, the former prison operated until 1971. Designed by John Haviland and opened in 1829, Eastern State is considered to be the world's first true penitentiary. Its revolutionary system of incarceration dubbed the "Pennsylvania system,” encouraged separate confinement in which guards were mandated to visit with each inmate three times a day as a form of rehabilitation. Photo by Carol Highsmith, 2019.