On May 9, 1799 a resolution was introduced at a meeting of the Freeholders that a work house be built at Mt, Holly and that the sum of four thousand dollars be raised. The resolution was postponed for a year, but it appears that there was much discussion as to the employment of prisoners while in confinement.

The next record concerning the building of a jail appears in the records of the board on May 13, 1807 when the two commissioners were appointed to purchase a lot in the town of Mt. Holly whereon a suitable county jail could be erected; the land was purchased from Zachariah Rossell and adjoined the court house property. These two commissioners were also to contract and procure materials for the jail and the sum of two thousand dollars was appropriated for that purpose. A new committee was appointed to provide a plan for the work house and the jail; this committee consisted of Charles Ellis, George Anderson, Daniel Hancock, Caleb Newbold, and Daniel Nowbold, During the year 1808, the committee on planning reported progress; the committee on material reported purchases have been made. On February 13, 1809 the committee appointed to procure a plan made a report to the board. Their report embodied the following recommendations:

Summary
The Eastern State Penitentiary, Philadelphia, Pennsylvania, is the prime exponent of the Pennsylvania system of imprisonment,, a system which was of limited influence in the United States, but was studied and applied widely in Europe and South America. This system, developed primarily by the Philadelphia Society for Alleviating the Miseries of Public Prisons, founded in 1787, was grounded in the Quaker concept of reflection in solitude as well as an abhorrence of the 18th century practice in Philadelphia of sentencing all offenders to public hard labor. In 1821, the state legislature appointed a building commission to oversee the construction of a 250-cell prison, based on the principle of solitary confinement. After a public competition for the design of the prison, won by; John Haviland, in 1823, the cornerstone was laid. Haviland's plan called for seven cellblocks radiating out of a common center, all enclosed by massive stone walls resembling medieval battlements. Each solitary cell had its own exercise yard and its own ventilation and lighting vent representing great improvements over previous prison facilities. The first prisoner was admitted in 1829, and for the next 85 years, with many enlargements and additions, the prison implemented the system of solitary confinement. In 1913 the system was abolished, and some 50 years later the penitentiary was closed. Today, it still stands at 21st and Fairmount Avenue, presenting much the same appearance as did in 1829.

History
The Eastern State Penitentiary in Philadelphia, which was built to apply the Pennsylvania System of imprisonment, served as a model for numerous other prisons throughout the world. Although of limited influence in the United States, the prison and the Pennsylvania System influenced, and continue to influence, penalogical practices in Europe, Asia, and Latin Americia.