St. Mary's City, Maryland is a former colonial town and was Maryland's first colonial settlement and capital. It is now a large, state-run historic area, reconstruction of the original colonial settlement, living history area and museum complex, also known as Historic St. Mary's City.
Half of the area is also the campus of the public honors college, St. Mary's College of Maryland.
St. Mary's City is the historic site of the founding of the Colony of Maryland (then called the Province of Maryland). The original settlement was also the fourth oldest permanent English settlement in the United States.
St. Marys City is also considered to be the birthplace of religious freedom in America, with the earliest North American colonial settlement ever established with the specific mandate of being a haven for both Catholic and Protestant Christian faiths.
It is also an internationally recognized archeological research area and training center for archaeologists,  and is home to the The Historical Archaeology Field School. There have been over 200 archeological digs in St. Marys city over the last 30 years. Archeological research continues in the city.
It is an unincorporated community under state law, and is located in Southern St. Mary's County, Maryland, which in turn is the southernmost tip of the state of Maryland on the Western shore of the Chesapeake Bay. St. Mary's City is bordered by the St. Mary's River, a short, brackish water tidal tributary of the Potomac river, near where it empties into the Chesapeake.