The Slate Belt


"These places, the intersection of geology, technology, and culture, were an important part of American life and their stories are still accessible through the visual testimony of the land, the structures, and the machinery, as well as the stories of those who last labored there."


Frank Matero - Project Director

Graduate Program in Historic Preservation - University of Pennsylvania

The Pennsylvania “Slate Belt,” an area of only 22 square miles, lies approximately 50 miles to the northwest of Philadelphia and just south of Blue (Kittanning) Mountain between the Delaware and Lehigh Rivers. The first quarries opened in the 1830s, but significant growth followed in the first decade of the twentieth century when Lehigh Valley accounted for approximately half the slate produced in the United States, eventually becoming the greatest slate producing region in the world.1

The Impetus

This project was originally conceived as a University of Pennsylvania studio class in the Graduate Program in Historic Preservation. With generous funding from the J. M. Kaplan Foundation, Professor Frank Matero and a group of 10 students began to investigate the history of the slate industry in Pennsylvania in response to public awareness that this valuable cultural landscape was being overlooked and disappearing. With the vast majority of the quarries of the region (more than 350 in total) having closed by the mid 1970's, the living legacy which maintained the methods for slate quarrying in the region, having not been passed to a new generation, was quickly disappearing. The student effort focused primarily on one quarry, American Bangor, which first opened in 1875 and still retains much of its original fabric including the incline cableways used to lift massive pieces of slate from within the quarries, and a system which was unique to the slate quarries of the Pennsylvania Slate Belt. Much of the data collected during this class has been incorporated into this website.


In conjunction with the efforts of the students and faculty at the University of Pennsylvania, was a team of students from Muhlenberg College. Professor Joseph Elliott and his studio from the Fine Arts Department chose to document both the current active quarries, as well as the residents of the communities that make up the Slate Belt district. The final result of that effort produced a web page called Slate Stories that showcased the photography and documentation carried out by the students.


Much of the information for this website has been collected, or quoted directly from primary documents that were created in response to, and as a result of the massive industry which existed for more than a century from the early 1830's until its ultimate demise during the decades after World War II, however the beginning of the end began long before that. During World War I, many of the slate firms closed to release men for other essential war work, especially in the Bethlehem Steel plant nearby. Most of the quarries that closed, never reopened after the war as modern synthetic materials such as asphalt composites and plastics proved less expensive and easier to use, and required less skilled labor to fabricate and install.


Since no single source of information is complete or infallible, the hope is that this site can continue to expand and be modified to reflect the growing wealth of historic information available about this subject.


The Altered Landscape

The Lehigh Valley’s extractive industries created a much altered landscape with vast and deep quarries, enormous kilns, and mill buildings in a complex landscape that allows for the exploration of architectural, ecological, and socio-cultural considerations. As proven elsewhere, this industrial legacy holds the key to revitalization of the region by “regeneration through heritage,” not only in the preservation and possible re-use of these sites, but as catalysts for reviving and maintaining the social and cultural fabric of their surrounding communities and natural environment. Cultural and environmental conservation become powerful partners in the reclamation of this complex place through ecological and social as well as architectural concerns.



Still Viable

Today only a handful of the old slate quarries remain active. Big Bed Slate, still in operation, is one of the oldest and best preserved of the early operations with its Victorian crane hoists, steam and electric machinery and mill shops, and extensive series of former and active quarries. This company, still economically viable, and interested in spearheading the valley’s industrial history, offers a unique opportunity together with the Slate Belt Heritage Center in Bangor, PA to document that legacy through a creative mix of preservation and economic development.

Pennsylvania’s slate belt exists within the Delaware and Lehigh National Heritage Corridor (D&LNHC), created in 1988. Despite this relationship, this conjoined landscape falls outside the Corridor’s main 165 mile trail and primary narrative dedicated to the coal, iron and steel industries and the canal and railroad networks that helped build them. This digital project seeks to work within the existing framework and partner with the D&LNHC to expand the potential of the Corridor and proposed area .

Image Source: Joseph Elliott

The incline cableway - Once a standard of the Pennsylvania slate industry, The three headframes at American Bangor are some of only standing systems in the entire Slate Belt region.

Industrial Legacy

Why invest in preserving these former industrial landscapes? As proven elsewhere, this industrial legacy holds the key to revitalization of the region by “regeneration through heritage,” not only in the preservation and possible re-use of these sites, but as catalysts for reviving and maintaining the social and cultural fabric of their surrounding communities and reclamation of the natural environment.

First, their continued physical existence is critical to understand how the region took shape physically, socially, economically, and culturally, more than any text or photograph can convey: real structures in real landscapes. Second, these early twentieth century sites extend the region and country’s industrial narrative from the classic eighteenth and nineteenth century notion of industrial heritage to those complexes that were responsible for America’s emergence as the world power by the latter twentieth century. Third, although the twentieth century is better documented than any other century in word and image, analog and digital, the industrial artifact and place, where they survive together, still remain the primary locus for analysis and interpretation.


"By taking a cultural landscape approach to the analysis and redevelopment of these overlapping industries, we acknowledge their original premise of natural resource extraction and exploitation in the deconstruction and construction of the land."


Cultural and environmental conservation become powerful partners in the reclamation of this complex place through ecological and social as well as architectural technological concerns.


In order to bring a more critical approach to the preservation of the most important and iconic of American industrial sites as recommended by the 2010 Symposium Industrial Heritage Retooled, this project proposed to address an important and understudied class of 20th century industrial heritage: the extractive industries.


"The intent is to produce a well-documented and methodologically driven website that clearly identifies the critical components of this neglected large-scale industrial landscape."


Acceptance of the geo-survey, mapping, and architectural documentation by HABS/HAER will be in itself confirmation of the value of the work. Additional leverage of the products of recording, analysis and assessment will be used to advocate support for preservation at the site and community level through exhibition, publication, and a public charrette. Web site access will help establish dissemination and influence of the findings of the project. Since the intent is to try to provide an accurate depiction of what the slate industry was, much of the content of this website has been extracted directly from sources which were written by people who had real life experience with the industry.An advisory committee including former PHMC director Brenda Barrett, Robert Melnick, Professor and former Dean of Landscape, University of Oregon, Fred Quivik, Professor of History at Michigan Technological University, and Shaun Eyring, Landscape architect. NPS will assist the project as needed. Partners in this project include: the National Park Service-Historic American Landscape Survey (HALS) and the Historic American Engineering Record (HAER) as well as the Pennsylvania Historical and Museum Commission, the Delaware and Lehigh National Heritage Corridor, and local community partners.



An advisory committee including former PHMC director Brenda Barrett, Robert Melnick, Professor and former Dean of Landscape, University of Oregon, Fred Quivik, Professor of History at Michigan Technological University, and Shaun Eyring, Landscape architect. NPS will assist the project as needed. Partners in this project include: the National Park Service-Historic American Landscape Survey (HALS) and the Historic American Engineering Record (HAER) as well as the Pennsylvania Historical and Museum Commission, the Delaware and Lehigh National Heritage Corridor, and local community partners.

1. Dale, N. 1914. Slate in the United States. Washington, DC: U.S. Government Printing Office.