Significance: Soon after its founding in 1899, the Republic Iron and Steel Company acquired the existing Haselton blast furnace and subsequently built four blast furnaces. These blast furnaces produced pig ir More
Significance: The Atomic Physics Observatory (APO) was completed in 1938 to improve the capability of measuring the earth's magnetic fields which was undertaken by the Carnegie Institution of Washington's Depar More
Significance: Typical southwestern Pennsylvania company town built to house miners and coke workers. Company store is one unique and is one of the best preserved of its type in the region. Survey number: HAER More
Significance: This building originally served as a foundry to cast nonferrous materials for tools, measuring instruments, and various fasteners and fittings used in magnetic observations undertaken the Carnegie More
Significance: Chicago city engineers employed their standard bascule design for this bridge carrying Canal Street Bridge across the South Branch of the Chicago River. Its streamlined bridgetender's house refle More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: The buildings of the Crawford Electric Generating Station were designed by the renowned architectural firm of Graham, Anderson, Probst and White; the Crawford Station also reflects the rapid expan More
Significance: Formed in 1857 as the Saconna Iron Company, this steel works along the Lehigh River was reorganized the following year as the Bethlehem Rolling Mill and Iron Company. Under the direction of Robert More
Significance: Formed in 1857 as the Saconna Iron Company, this steel works along the Lehigh River was reorganized the following year as the Bethlehem Rolling Mill and Iron Company. Under the direction of Robert More
Significance: Formed in 1857 as the Saconna Iron Company, this steel works along the Lehigh River was reorganized the following year as the Bethlehem Rolling Mill and Iron Company. Under the direction of Robert More
Significance: Formed in 1857 as the Saconna Iron Company, this steel works along the Lehigh River was reorganized the following year as the Bethlehem Rolling Mill and Iron Company. Under the direction of Robert More
Significance: Formed in 1857 as the Saconna Iron Company, this steel works along the Lehigh River was reorganized the following year as the Bethlehem Rolling Mill and Iron Company. Under the direction of Robert More
Significance: During peak production, Griffin No. 1 Coke Works operated one battery of double-block rectangular coke ovens. Sections of these ovens remain and are considered some of the best preserved rectangu More
Significance: During peak production, Griffin No. 1 Coke Works operated one battery of double-block rectangular coke ovens. Sections of these ovens remain and are considered some of the best preserved rectangu More
Significance: During peak production, Griffin No. 1 Coke Works operated one battery of double-block rectangular coke ovens. Sections of these ovens remain and are considered some of the best preserved rectangu More
Significance: During peak production, Griffin No. 1 Coke Works operated one battery of double-block rectangular coke ovens. Sections of these ovens remain and are considered some of the best preserved rectangu More
Significance: Built by the Royer family about 1810; John Royer settled in this area around 1805. Along with his brother Daniel, he established an iron furnace one-quarter mile to the south, on Piney Creek. The More
Significance: Built by the Royer family about 1810; John Royer settled in this area around 1805. Along with his brother Daniel, he established an iron furnace one-quarter mile to the south, on Piney Creek. The More
Significance: Built by the Royer family about 1810; John Royer settled in this area around 1805. Along with his brother Daniel, he established an iron furnace one-quarter mile to the south, on Piney Creek. The More
Significance: Built by the Royer family about 1810; John Royer settled in this area around 1805. Along with his brother Daniel, he established an iron furnace one-quarter mile to the south, on Piney Creek. The More
Significance: Built by the Royer family about 1810; John Royer settled in this area around 1805. Along with his brother Daniel, he established an iron furnace one-quarter mile to the south, on Piney Creek. The More
Significance: Ricks manufactured the Covington coke puller, the most widely-used mechanical coke-drawing machine in the Connellsville Region. Survey number: HAER PA-366 Building/structure dates: ca. 1900 Init More
Significance: Ricks manufactured the Covington coke puller, the most widely-used mechanical coke-drawing machine in the Connellsville Region. Survey number: HAER PA-366 Building/structure dates: ca. 1900 Init More
Significance: The Chicago & Alton Railroad bridge was the first Page bascule erected for railroad use. Patented by John W. Page, a Chicago engineer, the Page bascule was not as extensively built as other paten More
Significance: The Chicago & Alton Railroad bridge was the first Page bascule erected for railroad use. Patented by John W. Page, a Chicago engineer, the Page bascule was not as extensively built as other paten More
Significance: The Chicago & Alton Railroad bridge was the first Page bascule erected for railroad use. Patented by John W. Page, a Chicago engineer, the Page bascule was not as extensively built as other paten More
Significance: The Chicago & Alton Railroad bridge was the first Page bascule erected for railroad use. Patented by John W. Page, a Chicago engineer, the Page bascule was not as extensively built as other paten More
Significance: The Chicago & Alton Railroad bridge was the first Page bascule erected for railroad use. Patented by John W. Page, a Chicago engineer, the Page bascule was not as extensively built as other paten More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More
Significance: The Republic Iron and Steel Company installed a United-Tod twin-tandem compound steam engine and a Mesta-Corliss cross-compound steam engine in its blooming mill building at its Youngstown Works t More