Site Supervisor Rachael Reader from the University of Salford’s Centre for Applied Archeology told us what they hope to find.
The prison opened in Salford beside the River Irwell and next to what became New Bailey Street the foundation stone for a prison was laid down on 22 May 1787.
The stone was laid by Thomas Butterworth Bayley, after whom the prison was named.
From the New Bailey car park next to the site you can make out the brick foundations of the prison cells both male and female, the workshops, day room and the turnkey office.
The prison was built to the design of John Howard, a man famous for his work in prison reform and is credited with establishing the principle of single cells for inmates.
He also advocated that prisons should be healthy and clean places as well as a place of punishment.
Prisoners there were initially only serving six-month sentences but they were made to do such menial tasks as handloom weaving, oakum picking and rope weaving.
More serious offenders were made to power the dreaded treadwheel which entailed one or more prisoners stepping up and down to power the treadmill often for 10 hours a day or more.
The prison is notable for public executions which took place outside the prison gates, including the three Irishmen who would go down in history as The Manchester Martyrs.
You can read and watch much more about their fascinating tale here: Horrible History – The Manchester Martyrs, 1867
The last public execution took place in April 1868 when Timothy Faherty and Miles Weatherill took to the gallows.
The dig has already been given a boost by the gift of a trowel, maul (which is a large hammer) and a trowel used on the opening day by Thomas Butterworth Bayley.
These were donated by Freemason James Cale of The Lodge of Unanimity Number 89 in Dukinfield.
In 1866 a new prison was built in Manchester at Strangeways and the prisoners were transferred there and some time in 1868 it seems that the New Bailey prison closed.
The archaeological dig has taken four weeks and comes to a close after one final tour this Friday 27 March.
The 125,000sq ft One New Bailey office block will be built on top of the prison site as a permanent reminder of this most significant period in Salford’s social history.