The St. Mary's County Detention Center traces its history to the origins of the Sheriff's Office, established in 1637.  

The oldest Detention Center ("the Old Jail") was built in 1856.  

The Old Jail is located in Leonardtown, next to the Circuit Courthouse.  It now houses the offices of the St. Mary's County Historical Society.  

In front of the "Old Jail" you will find a cannon which was brought to Maryland in 1634 aboard the Ark, one of the first ships bringing settlers to Maryland.  You can tour the Old Jail, Monday thru Friday between noon and 4 pm.

The county constructed the next detention facility in 1945 as an addition to the Circuit Courthouse in Leonardtown.  This served the county from 1945 to 1989.  That building was razed in 1999 due to the Circuit Courthouse Expansion Project.

Due to the county's growth, it was necessary to construct a larger detention facility.  That facility is the present Detention Center that stands today behind the Carter Building in Leonardtown.  On May 12, 1998, the 62 bed expansion wing of the Detention Center was dedicated to William C. Gatton.

To recognize the opening of the Gatton Wing, as well as raise funds for the operation of the Detention Center, members of the Criminal Justice community and the general public were invited to "spend a night in jail."  This activity provided the Correctional Officer staff and the Emergency Response Team an excellent opportunity to familiarize themselves with the operation of the "new" unit.

The Gatton Wing ("E Pod") was opened and occupied in June of 1998.

St. Mary’s County Detention Center
41880 Baldridge Street
Leonardtown, Maryland 20650
301-475-4200 x3200
Click Here for the St. Mary's County Detention Center Visitor's Guide in PDF format.