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data quality statement 


The Cultural Resources Geographic Information System (CRGIS) is an easier way to access the data stored in Pennsylvania State Historic Preservation Office's (SHPO) files. Data include Archaeological Sites (PASS), Historic Resources, and Archaeological and Historic Survey Reports. In all cases, the data in the CRGIS are reflective of the quality of the data on the original paper forms. Absence of data does not necessarily indicate absence of resources. The CRGIS is an ongoing initiative, and tables and associated data will undergo staged enhancements and constant updating. As of September 2014, there are approximately 23,000 archaeological sites, 131,250 historic properties, and 10,300 survey reports in these files.

These inventories existed in electronic data files prior to the initiation of the CRGIS. All data collected in the PHMC databases prior to 1996 were imported from the original databases. Map locations were captured by digitizing the locations from the paper USGS 7.5' quadrangles.


Archaeological Sites

Data Sources

Sites are added to the Pennsylvania Archaeological Site Survey (PASS) whenever site forms are received from any source: avocational recorders, academic recorders, and cultural resource management (CRM) surveys. There has not been a full systematic archaeological survey of the Commonwealth. Environmental data for archaeological sites are often extrapolated from the maps. Locations are not field verified by SHPO personnel prior to inclusion.

Sites must meet our Site Identification Criteria to be included in the files with a Smithsonian trinomial, formatted as 36XX0000 where 36 represents Pennsylvania, the two letter code is the county designation, and the four numbers represent the sequence number of the site within the county. Isolated finds and non-site collections are designated by 36XX/000. These are generally locations where individual diagnostics were found, or where materials were collected that do not meet the site criteria, but were included in the curated collections from a project.


Archaeological sites that had map locations in 1996 are all located in the CRGIS. Approximately 300 site records had no map locations. All archaeological sites inventoried since 1996 have been digitized from the maps provided with the forms. All boundaries should be considered approximate unless the site has been fully excavated. Any site showing on the map as a small circle is represented by only a center point.

Sites are color coded on the mapping by their general site type of historic only, prehistoric only, or Multi-comp Prehist/Hist. This last indicates that the site has both historic and prehistoric materials and is not a combination of the other two categories. You must select all three to see all sites. In addition, we have begun to include isolated finds in the mapping. These are generally locations where individual diagnostics were found.

Data Status

Site characteristics from all pre-1996 site forms have been entered in the database. New sites are added as they arrive, with some delay due to work load. There is currently a 3 month backlog in entering and mapping new sites.

Site information frequently reflects only the initial investigation of the site. Information from subsequent excavations is added when provided, but many researchers do not submit updated forms.

Historic Resources

Date Sources

Properties are added whenever received from any source: systematic local surveys, CRM surveys, thematic studies, and individual property submissions for CRM review or National Register consideration. Only cultural information that was included by the original recorders or could be determined from the illustrations could be included. Many of the entries are old and reflect the time of recordation, not current conditions. Completeness of the data is dependent upon the reason for recordation. A record may be anything from a location and a single photo from a regional survey to full National Register listing documentation. County inventories vary in their age and completeness. 36 counties have had no systematic survey.

A group of railroad related "Aggregate Files" are included in the database, but not in the paper files. These records are digital files that were created as a means of bringing together, and displaying in the CRGIS, any previously surveyed components of a particular railroad line, noted in the details report as "Associated Resources." The historic paths of the lines are also mapped in the CRGIS, and a listing of each county and municipality that the rail line traveled through is provided. This will allow surveyors to quickly identify any previously surveyed resources in our files that are related to rail properties they are researching. Brief railroad histories, lineage files, have also been created from various sources, and will appear as a .pdf document within the CRGIS Aggregate File report display to further assist the user.


The completeness of the locational data in surveyed counties varies by county, based on the survey methodology. County by county, 75-95% of inventoried historic sites have mapped locations. The remaining un-mapped historic sites can be listed by the CRGIS for each municipality by doing a spatial query and selecting the "Unmapped Historic Sites" report. This report lists all unmapped historic resources in the database that are recorded within the same municipality(ies) as the selected area. All new submissions require mapping.

Historic sites are currently mapped by the resource that would be evaluated for the National Register of Historic Places. This means that, in the case of a district, the district boundaries would be mapped, not the individual buildings on the inventory. Prior to 1996, each building had its own keynumber and mapping. We are actively consolidating these data, but many of the older conditions still exist. Large numbers of resource with "undetermined" eligibility seen within a district boundary probably indicate such a case.

Historic resources are color coded on the maps to indicate the National Register status. Please see the legend for the designations.

Data Status

Resource characteristics from all pre-1996 site forms have been entered in the database. New individual properties are entered and mapped when received. There are some older surveys that were never entered into the database. New regional surveys received electronically may have a delay in the uploading process for data verification and conversion.

All National Register listed properties and National Historic Landmarks are mapped and have attached photographs and forms. Newer submissions may have images attached that were received digitally. Old forms are being scanned and attached to individual records, but this process will take many years to complete. Currently, the only scans are in Chester County.

Archaeological and Historic Survey Reports

Data Sources

Most of the survey reports are the result of Cultural Resource Management surveys. They are identified by their project file "ER Numbers" which have a format of YYYY-NNNN-CCC-A, where the first 4 digits are the year the project started, the second four are a sequence number within that year, the next three are the county code, and a final (optional) letter indicates the submission within that project.

Other report types include reports from regional surveys, multiple property nomination (thematic) documentation, historic context documents, and research papers. These have designations that are similar to the ER Numbers, but the sequence number in the middle will include a letter: R = archaeological research, H = historic non-project survey or research, and M = multiple property nominations.


Only Phase I surveys, geomorphological reports, negative survey forms, and records of disturbance are mapped. Since Phase IIs and IIIs are, by definition, within recorded sites, these reports are not mapped. Quality and granularity of the mapping is dependent upon the quality of the original mapping. Older reports tend to show only generalized areas. Newer reports will have specific testing areas mapped.

Historic Resource Survey Reports often cover entire municipalities or even counties, so we have chosen not to map them.

Data Status

Archaeological survey reports submitted prior to 1996 are mapped and included in the database. New reports are added to the database when reviewed, and mapped if appropriate. Abstracts are scanned and attached. Since these three operations are being conducted by separate groups, it is possible for a survey to be mapped, but have no data or to have data that can be found in the database search (Ask ReGIS), but not be mapped. Please remember that only certain report types are included in the mapping. There is currently a substantial backlog in both scanning and mapping. Exact delay is not definable, since it varies across the state. We have several data cleaning projects underway that lead to some areas being up-to-date while others may be 1-2 years behind.

Historic Resource Survey Reports were added to the database in 2010, with minimal data. We are actively working on updating these data and scanning abstracts. New reports are added as they are reviewed.