A Place in Time spotlights a significant cultural resource - a district, site, building, structure or object - entered in the National Register of Historic Places.
Living surface dating to the Late Archaic Period at Calver Island. KCI Technologies Inc.

Living surface dating to the Late Archaic Period at Calver Island. KCI Technologies Inc.

With the passage of the National Historic Preservation Act 50 years ago, the federal government asserted that “the historical and cultural foundations of the nation should be preserved as a living part of our community life and development in order to give a sense of orientation to the American people.” These foundations exist not only aboveground but also belowground – the realm of archaeological history and prehistory. Aside from simply recognizing the importance of this heritage, the law provided a mechanism to give archaeological sites consideration during the process of planning federal projects. Known as “Section 106,” this regulation requires federal agencies to take into account the effects of their undertakings on any properties listed or eligible for listing in the National Register of Historic Places. As part of this process, the federal agency is responsible for identifying these properties and avoiding, minimizing or mitigating adverse effects on them.

Section 106 consultation often ends with an agency redesigning a project to avoid the site altogether. In cases where impacts cannot be avoided, the only choice is to excavate a robust sample of the site so that the information contained in it can be preserved for present (and future) study; however, excavation actually destroys the site. It may seem paradoxical, but the current practice of archaeologists leans toward avoidance – refraining from excavating and thus destroying a site, unless there is no other option. In very rare instances, archaeologists are able to excavate and preserve a site for future generations.

A roasting pit from the Transitional Period at Calver Island. KCI Technologies Inc.

In the early 2000s a Pennsylvania Turnpike Commission project on Calver Island, Dauphin County, in the Susquehanna River required a U.S. Army Corps of Engineers (USACE) permit, triggering Section 106 review. The site had been identified by a collector in the 1970s and a portion of it was going to be impacted by the project. Based on additional excavations, USACE in consultation with Pennsylvania’s State Historic Preservation Office found that Calver Island (designated site 36Da89) was eligible for listing in the National Register of Historic Places because of the information it contained. (This by the way is why most archaeological sites are eligible for the National Register.) Intensive excavations were conducted to mitigate the effects of the project impacts, but enough of the site remained undisturbed that it could still be nominated to the National Register.

The site was stratified, meaning that it had been occupied multiple times and that the inhabitations were stacked one on top of the other. In other words, one group lived at the site for a time and moved on; floodwaters covered the remains of the encampment with silt; then another group arrived and occupied the site, which was later covered with more silt from floodwaters; and so on. At Calver Island, this sequence occurred multiple times within the Late Archaic Period (approximately 4,300 to 6,000 years ago), the Transitional Period (approximately 2,700 to 4,300 years ago) and the Early Woodland Period (approximately 2,100 to 2,700 years ago). Of course, these “periods” are arbitrary constructs to help archaeologists understand past human behavior by grouping together characteristics, including similar settlement patterns, tool types, population and trade networks. Arbitrary or not, taken together the occupations from each of these periods at Calver Island provide the archaeologist with important information on how culture changed within and among these periods, adding to our knowledge of when trade networks flourished (from the presence of tools made from nonlocal stone), how diet changed (from the remains of certain plants such as squash), how tools were used (from microscopic analysis of wear patterns on tools, indicating for example that they were used to butcher animals or work wood) and so forth.

Based on the information recovered and the fact that enough of the site remained for future archaeologists to learn even more, Calver Island was listed in the National Register and made a state-owned archaeological preserve. As the late archaeologist Charles R. McGimsey III put it in his seminal work Public Archaeology, “No one owns exclusive rights to … archaeological data any more than the owner of a Rembrandt has exclusive rights to that painting.” State ownership of Calver Island through the Pennsylvania Turnpike Commission ensures that the right to understand our shared history is held in trust for all of us.


Recent listings in the National Register of Historic Places include Bethel Burial Ground, Philadelphia; Loyalhanna Lodge No. 275, Latrobe, Westmoreland County; Nesbit-Walker Farm, Canton Township, Washington County; Pittsburgh Brass Manufacturing Co. Building, Pittsburgh, Allegheny County; Plantation Plenty (Boundary Increase), Independence Township, Washington County; Salvation Army Building, Pittsburgh, Allegheny County; David Slusher Farm, Amwell Township, Washington County; and Temple Ohave Israel, Brownsville, Fayette County.


Keith Heinrich is a historic preservation specialist who coordinates the National Register Program for the western part of Pennsylvania at PHMC’s State Historic Preservation Office.