St. Mary’s City, MD- According to a letter written by Governor Leonard Calvert in May 1634, the colonists settled “within one-half mile of the river, within a pallizado of one hundred and twentie yarde square, with four flankes.” The fort was also mentioned in a brief description included in a pamphlet based on the writings of Father Andrew White called A Relation of Maryland.
Based on these descriptions, Historic St. Mary’s City (HSMC) staff believed that St. Mary’s Fort was likely constructed in one of two locations: the ‘traditional site’ (south of Town Center, near the Print Shop) or a 15-acre tract known as Mill Field, which is further inland but lies along a creek that would have been deeper and more navigable by small vessels in the early 17th century. Early 17th-century artifacts had been found in both areas during previous archaeological investigations and both seemed promising.




The mystery lingered until In 2017, when Director of Research and Collections Dr. Travis Parno, decided to resume the search for St. Mary’s Fort. HSMC secured a Non-Capital Grant from the Maryland Historical Trust, with matching funds provided by the Historic St. Mary’s City Foundation for a new phase of exploration. The grant funds were used to hire expert geophysicist, Dr. Timothy J. Horsley of Horsley Archaeological Prospection, LLC to conduct a geophysical survey of both the traditional site and the Mill Field. Dr. Horsley’s survey used three methodologies: magnetic susceptibility, magnetometry, and ground-penetrating radar.
Thanks to the grant from Maryland Historical Trust and the work of Dr. Timothy J. Horsley, evidence showed the location of the fort to be the Mill field, sparking a further investigation that promises to give us information about the colonists that arrived in Maryland, and of the peoples who were here before them.
To hear further about the find, and about our exciting new project be sure to watch our the premiere of our announcement on March 25, 7 p.m. The program will stream on https://www.hsmcdigshistory.org/events/maryland-day