The Simpsonville Mill Site (18HO80) is a late 18th- through early 20th-century mill town on the Middle Patuxent River in Howard County, Maryland. Two 19th-century maps depict a rural milling community with a gristmill, a woolen factory, a sawmill, a general store, a wheelwright shop, a blacksmith shop, a cemetery, and at least nine residences. Simpsonville Mill served a variety of needs, including flour milling and textile production, and functioned as a town center for over two hundred years.

The Simpsonville Mill Archaeological and Historic District represents one of the few mill sites in Maryland that has been professionally investigated. It is an important example of how smaller industrial and commercial centers operated within the regional economic system of the grain and textile industry in Maryland between ca. 1790-1930. Furthermore, the mill’s use of a breast wheel for power makes its construction distinct when compared to other contemporary gristmills.

Archaeological Investigations

In 1984, Lee Preston led the Upper Patuxent Archeology Group and a group of students from Atholton High School in excavations at the supposed location of the Iglehart General Store in Simpsonville. They dug 72 one-by-one-meter units and recovered numerous artifacts dating from the late 19th and early 20th centuries.

In 1987, Richard Ervin and Spencer Geasey of the Maryland Geological Survey undertook a Phase I survey of Simpsonsville Mill prior to proposed highway construction. Their methodology included a surface inspection of exposed soils and fields, and the excavation of five shovel test pits measuring 40 centimeters in diameter. Two shovel test pits were placed randomly, while the other three were located on an earthen terrace near two recently-identified features designated 3 and 5. All soil was screened through ¼-inch hardware mesh, with all artifacts retained for analysis. This investigation identified 16 additional features, many which were visible on the surface, including the stone walls of the mill and other structural foundations.

GAI Consultants undertook the Phase II investigation of the Simpsonville Mill Site from November 1989 to January 1990. Two hundred and thirty shovel test pits measuring 50 centimeters in diameter were dug to a depth of at least one meter over the entire site. Within the proposed right-of-way, shovel tests were excavated at five and ten-meter intervals, while shovel tests were dug at ten-meter intervals outside the impact zone. Twenty-nine one-by-one-meter test units, dug in 10 centimeter levels within natural strata, were also excavated in areas of high artifact concentration or around structural features. In addition, a magnetometer survey collected data in five areas to identify subsurface features. A total of 47 features were identified during Phase II investigations, some in intact, stratified, archaeological deposits.

John Milner Associates conducted the Phase III investigation of the sections of the Simpsonville Mill Site within the highway right-of-way between October 1992 and February 1993. One hundred and seventy-six shovel tests, 30 centimeters in diameter, were excavated stratigraphically. Forty-four excavation units, most measuring one-by-one meter, were excavated following natural strata, with 10 centimeter arbitrary levels used in thick strata. All shovel tests and excavation units were excavated to sterile soil and screened through ¼-inch mesh. Three-liter flotation samples were also taken from features. In addition, column soil samples were taken for flotation from the five backhoe trenches across the mill waste race, overflow race, tailrace, and headrace, and between the tailrace and the overflow race. The Phase III investigations concentrated on architectural analysis and data recovery from the stone foundation of the mill/woolen factory, the overflow or waste race, the gristmill, an early wheelpit wall, Iglehart’s General Store, and an unidentified stone foundation.


Over 42,000 artifacts were recovered from the Simpsonville Mill Site. These materials suggested that few activities other than industrial endeavors occurred within and around the mill buildings. A predominance of architectural objects characterize the artifacts from Simpsonville Mill, including window glass, nails, and other fasteners, while artifacts relating to food preparation and other activities were less common. Within the gristmill, architectural items make up three-quarters of the assemblage, followed by kitchen objects, unidentified machinery parts and tools, clothing artifacts, and two millstones. The stone foundation and the site of Iglehart’s General Store produced similar results, with a large number of architectural artifacts, but kitchen items constituted a larger percentage of the assemblage. A large number of lamp glass fragments were recovered from the general store. The small number of ceramic vessels, bottles, and glass tableware at the general store reveal minimal domestic activity occurred there, and probably reflect broken merchandise


The Simpsonville Mill record collection is comprised entirely of photocopies in good condition with excellent clarity, although the reverse sides of some documents are missing. The records are housed in three letter-sized archival clamshell boxes and one oversized enclosure.

Records exist for the Phase II and III investigations and include shovel test data sheets, unit level excavation forms and their associated plan and profile drawings, soil description forms, excavation unit records, feature record forms, feature summary records, and feature plan and profile drawings.

The Phase II excavation records are organized by STP data, test units, and features, and are arrange sequentially by number. The Phase II excavation records are organized by ‘operations,’ which were assigned numerical values and refer to different locations within the site. Not all operations were included in the current digitization project; however, these unscanned records (operations 2 and 4) have been kept physically with the rest of the collection and organized in the same manner. The digital organization reflects the above physical organization. It should be noted that within operation 13, both units 8 and 9 have the same coordinates according to excavation unit records; no site map or other documentation was found to establish the true coordinates for each.

Other records include field specimen logs; feature, photo and stratigraphic logs; and maps. These have been scanned as .PDF files and are not word searchable. There are two bound reports available online as word searchable .PDF files: Phase II Archaeological Investigations at the Simpsonville Stone Ruins (18HO80) and the Heritage Heights Site (18HO149), Howard County, Maryland (Beynon and Irion 1990), and Data Recovery Investigations, Simpsonville (18HO80), Howard County, Maryland (Seifert et al. 1994).

Photographs taken on-site or in post-processing are available through the online database, and are searchable using the above criteria. Researchers should note that images are not linked directly to specific documents, and photograph records do not necessarily exist for all features or units. Original images consist of slides, prints, and contact sheets and are housed at the MAC Lab.


Beynon, Diane E. and Jack B. Irion
1990     Phase II Archaeological Investigations at the Simpsonville Stone Ruins (18HO80) and the Heritage Heights Site (18HO149), Howard County, Maryland. Appendices. Report prepared for the Maryland State Highway Administration.
Ervin, Richard G.
1989     Archeological Survey of Maryland Route 32 Between Pindell School Road and Maryland Route 108, Howard County, Maryland. Maryland Geological Survey Division of Archaeology File Report 238. Prepared for the Maryland State Highway Administration.
Seifert, Donna J., Elizabeth J. Abel, Douglas C. McVarish, and Dana B. Heck
1994     Data Recovery Investigations, Simpsonville (18HO80), Howard County, Maryland. Maryland State Highway Administration Archeological Report 99. Prepared for the Maryland Department of Transportation.

Digital Resources



Archaeological Report
Artifact Documents
Excavation Documents
Field Notes
Field Specimen Logs
  • Maps (11 pages, 7.65 MB)
Photo Log
Project Documents

Thank you for visiting our web site. If you have any questions, comments,
or new information to share, please contact us at

An online archive of over 30 archaeological sites in Maryland, produced by the Maryland Archaeological Conservation Lab with the support of the National Endowment of the Humanities.