Gadsby, David A.Shackel, Paul A.In the fall of 2009, archaeologists and students from the University of Maryland’s Center for Heritage Resource Studies, in conjunction with the Archaeology Program, Maryland National Capital Parks and Planning Commission, conducted phase II archaeological testing of a portion of the garden at the Federal-period Riversdale Mansion (18PR390). The goal of the excavation was to evaluate the impact of ongoing erosion on archaeological resources in the project area. Excavators dug a total of 4 units measuring five-foot square and another half-unit measuring 2.5-feet by five-feet. They recovered 4280 objects ranging in date from the early 19th century through the twentieth century. They also unearthed the remains of a large garden wall erected around 1805 as well as the foundation of a brick structure built before 1830. This report details the project activities, and recommends that M-NCCP continue to monitor the effects of erosion on these resources. It also suggests future research questions, should additional excavations prove necessary.en-USArchaeologyMarylandRiversdaleTechnical Report