Upper Mississippi River 9-Foot Channel, Lock & Dam No. 6, Trempealeau,...
Significance: The Upper Mississippi River Lock and Dam Project represents one of the largest and most ambitious of such undertakings. With roots in the Progressive Era, the project was adopted by New Deal prop... More
Upper Mississippi River 9-Foot Channel, Lock & Dam No. 6, Trempealeau,...
Significance: The Upper Mississippi River Lock and Dam Project represents one of the largest and most ambitious of such undertakings. With roots in the Progressive Era, the project was adopted by New Deal prop... More
Upper Mississippi River 9-Foot Channel, Lock & Dam No. 6, Trempealeau,...
Significance: The Upper Mississippi River Lock and Dam Project represents one of the largest and most ambitious of such undertakings. With roots in the Progressive Era, the project was adopted by New Deal prop... More
Upper Mississippi River 9-Foot Channel, Lock & Dam No. 6, Trempealeau,...
Significance: The Upper Mississippi River Lock and Dam Project represents one of the largest and most ambitious of such undertakings. With roots in the Progressive Era, the project was adopted by New Deal prop... More
Upper Mississippi River 9-Foot Channel, Lock & Dam No. 6, Trempealeau,...
Significance: The Upper Mississippi River Lock and Dam Project represents one of the largest and most ambitious of such undertakings. With roots in the Progressive Era, the project was adopted by New Deal prop... More
Napa River Railroad Bridge, Spanning Napa River, east of Soscol Avenue...
Significance: The Napa Valley Railroad Bridge served as an integral element of the Napa Valley Railroad. The importance of the railroad to the development of both the community of Napa and the surrounding regi... More
Penobscot Bridge, Spanning Penobscot River at Route 15, Bangor, Penobs...
Significance: This bridge is the last remaining Baltimore (Petit) through-truss bridge in the state. The current structure represents three different phases of construction: Phase 1 - the center span was erec... More
Penobscot Bridge, Spanning Penobscot River at Route 15, Bangor, Penobs...
Significance: This bridge is the last remaining Baltimore (Petit) through-truss bridge in the state. The current structure represents three different phases of construction: Phase 1 - the center span was erec... More
Penobscot Bridge, Spanning Penobscot River at Route 15, Bangor, Penobs...
Significance: This bridge is the last remaining Baltimore (Petit) through-truss bridge in the state. The current structure represents three different phases of construction: Phase 1 - the center span was erec... More
Chicago River Bascule Bridge, Clarke Street, Spanning Chicago River at...
Significance: The development of the Chicago trunnoin bascule bridge occurred during the first three decades of the twentieth century. Despite the controversy over patent infringement Joseph E. Strauss charg... More
Liberty Memorial Bridge, Spanning Missouri River at I-94, Bismarck, Bu...
Significance: The Liberty Memorial Bridge is a three-span, Warren-Turner through truss bridge, a variation of the Warren through truss designed by C.A.P. Turner. This was the first highway bridge over the Miss... More
Liberty Memorial Bridge, Spanning Missouri River at I-94, Bismarck, Bu...
Significance: The Liberty Memorial Bridge is a three-span, Warren-Turner through truss bridge, a variation of the Warren through truss designed by C.A.P. Turner. This was the first highway bridge over the Miss... More
Gault Bridge, Spanning Deer Creek at South Pine Street, Nevada City, N...
Significance: The Gault Bridge has been determined eligible for the National Register of Historic Places under criterion c for its significance in the history of bridge technology in California (Caltrans Bridge... More
Gault Bridge, Spanning Deer Creek at South Pine Street, Nevada City, N...
Significance: The Gault Bridge has been determined eligible for the National Register of Historic Places under criterion c for its significance in the history of bridge technology in California (Caltrans Bridge... More
U.S. Steel Edgar Thomson Works, Along Monongahela River, Braddock, All...
Significance: Named after the president of the Pennsylvania Railroad and early financial backer of the enterprises, was the first integrated Bessener steel works constructed in the Pittsburgh district by Andrew... More
Post Road Bridge, State Route 7-A, Havre de Grace, Harford County, MD
Significance: The bridge, a subdivided Pratt through truss commonly known as a Baltimore truss with substruts and subties, is an example of an early truss form developed for use on long spans. The bridge was f... More
Post Road Bridge, State Route 7-A, Havre de Grace, Harford County, MD
Significance: The bridge, a subdivided Pratt through truss commonly known as a Baltimore truss with substruts and subties, is an example of an early truss form developed for use on long spans. The bridge was f... More
South Street Bridge, Spans Pennsylvania Avenue, Wilkes-Barre Boulevard...
Significance: The South Street Bridge is an unusual, long span metropolitan bridge comprising thirteen concrete spans and two steel truss spans. While the concrete spans are representative, the trusses are unu... More
South Street Bridge, Spans Pennsylvania Avenue, Wilkes-Barre Boulevard...
Significance: The South Street Bridge is an unusual, long span metropolitan bridge comprising thirteen concrete spans and two steel truss spans. While the concrete spans are representative, the trusses are unu... More
South Street Bridge, Spans Pennsylvania Avenue, Wilkes-Barre Boulevard...
Significance: The South Street Bridge is an unusual, long span metropolitan bridge comprising thirteen concrete spans and two steel truss spans. While the concrete spans are representative, the trusses are unu... More
South Street Bridge, Spans Pennsylvania Avenue, Wilkes-Barre Boulevard...
Significance: The South Street Bridge is an unusual, long span metropolitan bridge comprising thirteen concrete spans and two steel truss spans. While the concrete spans are representative, the trusses are unu... More
South Street Bridge, Spans Pennsylvania Avenue, Wilkes-Barre Boulevard...
Significance: The South Street Bridge is an unusual, long span metropolitan bridge comprising thirteen concrete spans and two steel truss spans. While the concrete spans are representative, the trusses are unu... More
Burlington Northern Railroad Bridge, Spanning Willamette River at Rive...
Significance: Willamette River Bridge 5.1 is the south end part of a 4-3/4 mile-long network of railroad bridges, causeways, and cut system linking the mainlines north and south of Portland. The bridge is one ... More
Burlington Northern Railroad Bridge, Spanning Willamette River at Rive...
Significance: Willamette River Bridge 5.1 is the south end part of a 4-3/4 mile-long network of railroad bridges, causeways, and cut system linking the mainlines north and south of Portland. The bridge is one ... More
Burlington Northern Railroad Bridge, Spanning Willamette River at Rive...
Significance: Willamette River Bridge 5.1 is the south end part of a 4-3/4 mile-long network of railroad bridges, causeways, and cut system linking the mainlines north and south of Portland. The bridge is one ... More
Burlington Northern Railroad Bridge, Spanning Willamette River at Rive...
Significance: Willamette River Bridge 5.1 is the south end part of a 4-3/4 mile-long network of railroad bridges, causeways, and cut system linking the mainlines north and south of Portland. The bridge is one ... More
Burlington Northern Railroad Bridge, Spanning Willamette River at Rive...
Significance: Willamette River Bridge 5.1 is the south end part of a 4-3/4 mile-long network of railroad bridges, causeways, and cut system linking the mainlines north and south of Portland. The bridge is one ... More
Burlington Northern Railroad Bridge, Spanning Willamette River at Rive...
Significance: Willamette River Bridge 5.1 is the south end part of a 4-3/4 mile-long network of railroad bridges, causeways, and cut system linking the mainlines north and south of Portland. The bridge is one ... More
Blue Water Bridge Plaza, 410 Elmwood Street, Port Huron, St. Clair Cou...
Significance: The bridge and plaza were completed in 1938. They are reflections of Depression-era engineering and architecture. The plaza was designed and built by George L. Harvey and Norman B. Forbes. The ... More
Blue Water Bridge Plaza, 410 Elmwood Street, Port Huron, St. Clair Cou...
Significance: The bridge and plaza were completed in 1938. They are reflections of Depression-era engineering and architecture. The plaza was designed and built by George L. Harvey and Norman B. Forbes. The ... More
Three Sisters Bridges, Sixth Street Bridge, Spanning Allegheny River a...
Significance: The Three Sisters Bridges represent an adaptive engineering design response to political and technical concerns. County engineers successfully maneuvered around federally-mandated clearances, aest... More
New York, New Haven & Hartford Railroad, Groton Bridge, Spanning Thame...
Significance: The Groton Bridge is a Strauss heel trunnion bascule bridge. It is significant as part of the transportation link in the shoreline route of the New York, New Haven and Hartford Railroad, and as a... More
U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela Rive...
See also HAER PA-115 for additional documentation. Includes written data (pages 55 through 158). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward integ... More
U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela Rive...
See also HAER PA-115 for additional documentation. Includes written data (pages 55 through 158). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward integ... More
U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela Rive...
See also HAER PA-115 for additional documentation. Includes written data (pages 55 through 158). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward integ... More
U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela Rive...
See also HAER PA-115 for additional documentation. Includes written data (pages 55 through 158). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward integ... More
U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela Rive...
See also HAER PA-115 for additional documentation. Includes written data (pages 55 through 158). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward integ... More
U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela Rive...
See also HAER PA-115 for additional documentation. Includes written data (pages 55 through 158). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward integ... More
U.S. Steel Duquesne Works, Blast Furnace Plant, Along Monongahela Rive...
See also HAER PA-115 for additional documentation. Includes written data (pages 55 through 158). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward integ... More
Pennsylvania Railroad, West Philadelphia Elevated, Parallel to Schuylk...
See also HAER PA-71 for related documentation. Includes photographs. Significance: The West Philadelphia Elevated, part of the Pennsylvania Railroad's program to separate passenger and freight traffic, includes... More
Pennsylvania Railroad, West Philadelphia Elevated, Parallel to Schuylk...
See also HAER PA-71 for related documentation. Includes photographs. Significance: The West Philadelphia Elevated, part of the Pennsylvania Railroad's program to separate passenger and freight traffic, includes... More
Pennsylvania Railroad, West Philadelphia Elevated, Parallel to Schuylk...
See also HAER PA-71 for related documentation. Includes photographs. Significance: The West Philadelphia Elevated, part of the Pennsylvania Railroad's program to separate passenger and freight traffic, includes... More
North Side Point Bridge, Spanning Allegheny River at Point of Pittsbur...
See also HAER PA-3 for additional documentation. Includes written data. Significance: The Manchester Bridge replaced the old wooden Union Bridge, the first bridge erected at the Point and demolished in 1907. B... More
U.S. Steel Duquesne Works, Fuel & Utilities Plant, Along Monongahela R...
See also HAER PA-115 for additional documentation. Includes written data (pages 239 through 248). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward inte... More
U.S. Steel Duquesne Works, Fuel & Utilities Plant, Along Monongahela R...
See also HAER PA-115 for additional documentation. Includes written data (pages 239 through 248). Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward inte... More
Blue Water Bridge, Spanning St. Clair River at I-69, I-94, & Canadian ...
Significance: When it opened in October 1938, the Blue Water Bridge symbolized the peaceful relationship between the United States and Canada, a sharp contrast to the hostilities in Europe which were about to e... More
Blue Water Bridge, Spanning St. Clair River at I-69, I-94, & Canadian ...
Significance: When it opened in October 1938, the Blue Water Bridge symbolized the peaceful relationship between the United States and Canada, a sharp contrast to the hostilities in Europe which were about to e... More
Blue Water Bridge, Spanning St. Clair River at I-69, I-94, & Canadian ...
Significance: When it opened in October 1938, the Blue Water Bridge symbolized the peaceful relationship between the United States and Canada, a sharp contrast to the hostilities in Europe which were about to e... More
Blue Water Bridge, Spanning St. Clair River at I-69, I-94, & Canadian ...
Significance: When it opened in October 1938, the Blue Water Bridge symbolized the peaceful relationship between the United States and Canada, a sharp contrast to the hostilities in Europe which were about to e... More
Bellows Falls Arch Bridge, Spanning Connecticut River, North Walpole, ...
Significance: When built, the bridge was the longest single span highway bridge in the U.S. and is was among the largest three-hinged arch bridges in the world. The structure has also played an important role i... More
Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, ...
Significance: The Greenville Yard Transfer Bridge System is the last surviving example in New York Harbor of a suspended-type car float transfer bridge. The innovative design of the transfer bridge was introdu... More
Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, ...
Significance: The Greenville Yard Transfer Bridge System is the last surviving example in New York Harbor of a suspended-type car float transfer bridge. The innovative design of the transfer bridge was introdu... More
Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, ...
Significance: The Greenville Yard Transfer Bridge System is the last surviving example in New York Harbor of a suspended-type car float transfer bridge. The innovative design of the transfer bridge was introdu... More
Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, ...
Significance: The Greenville Yard Transfer Bridge System is the last surviving example in New York Harbor of a suspended-type car float transfer bridge. The innovative design of the transfer bridge was introdu... More
Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, ...
Significance: The Greenville Yard Transfer Bridge System is the last surviving example in New York Harbor of a suspended-type car float transfer bridge. The innovative design of the transfer bridge was introdu... More
Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, ...
Significance: The Greenville Yard Transfer Bridge System is the last surviving example in New York Harbor of a suspended-type car float transfer bridge. The innovative design of the transfer bridge was introdu... More
Greenville Yard, Transfer Bridge System, Port of New York/New Jersey, ...
Significance: The Greenville Yard Transfer Bridge System is the last surviving example in New York Harbor of a suspended-type car float transfer bridge. The innovative design of the transfer bridge was introdu... More
Eighteenth Street Bridge, Saint Louis, Independent City, MO
Significance: The Eighteenth Street Bridge is a 1,054-foot-long through-truss and through-plate girder structure with distinctive ornamentation over each truss portal in the form of finials and cresting, and pe... More
Eighteenth Street Bridge, Saint Louis, Independent City, MO
Significance: The Eighteenth Street Bridge is a 1,054-foot-long through-truss and through-plate girder structure with distinctive ornamentation over each truss portal in the form of finials and cresting, and pe... More
San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Fran...
Significance: The San Francisco-Oakland Bay Bridge is one of the most impressive engineering structures in the United States. It is also one of the most important transportation links in the United States, ser... More
San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Fran...
Significance: The San Francisco-Oakland Bay Bridge is one of the most impressive engineering structures in the United States. It is also one of the most important transportation links in the United States, ser... More
San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Fran...
Significance: The San Francisco-Oakland Bay Bridge is one of the most impressive engineering structures in the United States. It is also one of the most important transportation links in the United States, ser... More
San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Fran...
Significance: The San Francisco-Oakland Bay Bridge is one of the most impressive engineering structures in the United States. It is also one of the most important transportation links in the United States, ser... More
San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Fran...
Significance: The San Francisco-Oakland Bay Bridge is one of the most impressive engineering structures in the United States. It is also one of the most important transportation links in the United States, ser... More
San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Fran...
Significance: The San Francisco-Oakland Bay Bridge is one of the most impressive engineering structures in the United States. It is also one of the most important transportation links in the United States, ser... More
San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Fran...
Significance: The San Francisco-Oakland Bay Bridge is one of the most impressive engineering structures in the United States. It is also one of the most important transportation links in the United States, ser... More
San Francisco Oakland Bay Bridge, Spanning San Francisco Bay, San Fran...
Significance: The San Francisco-Oakland Bay Bridge is one of the most impressive engineering structures in the United States. It is also one of the most important transportation links in the United States, ser... More
Bush Terminal Company, Pier 5, Opposite end of Forty-first Street on U...
Significance: Pier 5 was typical of the substructures and piersheds built by Irving Bush c. 1902-09, sheet-piling-retained fill. It survives partly intact, and retains the best evidence of late attempts to mod... More
Choctaw Bottoms Road Bridge, Spanning Choctaw Creek at Choctaw Bottoms...
Significance: The Choctaw Bottoms Road Bridge is one of two extant bridges in Texas known to have been erected by the American Bridge Company of New York, a major twentieth-century bridge building firm. Survey... More
St. Charles Air Line Bridge, Spanning South Branch of Chicago River, n...
Significance: Like all Strauss heel-trunnion bascule bridges, the St. Charles Air Line Bridge rotates vertically, lifting to clear the river it spans. This particular bridge is unique, however, in that its des... More
Steel Bridge, Spanning Willamette River at State Route 99, Portland, M...
Significance: An early example of the Waddell-type vertical lift bridge, the Steel Bridge documents that, guided by Harrington, most features of the type achieved "standard" form by 1912. It also demonstrates ... More
Steel Bridge, Spanning Willamette River at State Route 99, Portland, M...
Significance: An early example of the Waddell-type vertical lift bridge, the Steel Bridge documents that, guided by Harrington, most features of the type achieved "standard" form by 1912. It also demonstrates ... More
Steel Bridge, Spanning Willamette River at State Route 99, Portland, M...
Significance: An early example of the Waddell-type vertical lift bridge, the Steel Bridge documents that, guided by Harrington, most features of the type achieved "standard" form by 1912. It also demonstrates ... More
Steel Bridge, Spanning Willamette River at State Route 99, Portland, M...
Significance: An early example of the Waddell-type vertical lift bridge, the Steel Bridge documents that, guided by Harrington, most features of the type achieved "standard" form by 1912. It also demonstrates ... More
Steel Bridge, Spanning Willamette River at State Route 99, Portland, M...
Significance: An early example of the Waddell-type vertical lift bridge, the Steel Bridge documents that, guided by Harrington, most features of the type achieved "standard" form by 1912. It also demonstrates ... More
Sparkman Street Bridge, Spanning Cumberland River, Nashville, Davidson...
Significance: The bridge possesses state level engineering significance as an example of the through Parker and camelback truss types for its uncommon concrete trusses. The bridge possesses local significance a... More
Sparkman Street Bridge, Spanning Cumberland River, Nashville, Davidson...
Significance: The bridge possesses state level engineering significance as an example of the through Parker and camelback truss types for its uncommon concrete trusses. The bridge possesses local significance a... More
Baltimore & Ohio Railroad, Harpers Ferry Station, Potomac Street, Harp...
Significance: The train station at Harpers Ferry provides an excellent opportunity to study the relationship between railroad engineering and railroad economics. Designed by architect E. Francis Baldwin, the s... More
Baltimore & Ohio Railroad, Harpers Ferry Station, Potomac Street, Harp...
Significance: The train station at Harpers Ferry provides an excellent opportunity to study the relationship between railroad engineering and railroad economics. Designed by architect E. Francis Baldwin, the s... More
Baltimore & Ohio Railroad, Harpers Ferry Station, Potomac Street, Harp...
Significance: The train station at Harpers Ferry provides an excellent opportunity to study the relationship between railroad engineering and railroad economics. Designed by architect E. Francis Baldwin, the s... More
Baltimore & Ohio Railroad, Harpers Ferry Station, Potomac Street, Harp...
Significance: The train station at Harpers Ferry provides an excellent opportunity to study the relationship between railroad engineering and railroad economics. Designed by architect E. Francis Baldwin, the s... More
Baltimore & Ohio Railroad, Harpers Ferry Station, Potomac Street, Harp...
Significance: The train station at Harpers Ferry provides an excellent opportunity to study the relationship between railroad engineering and railroad economics. Designed by architect E. Francis Baldwin, the s... More
Baltimore & Ohio Railroad, Harpers Ferry Station, Potomac Street, Harp...
Significance: The train station at Harpers Ferry provides an excellent opportunity to study the relationship between railroad engineering and railroad economics. Designed by architect E. Francis Baldwin, the s... More
Baltimore & Ohio Railroad, Harpers Ferry Station, Potomac Street, Harp...
Significance: The train station at Harpers Ferry provides an excellent opportunity to study the relationship between railroad engineering and railroad economics. Designed by architect E. Francis Baldwin, the s... More
Mystic River Bridge, Spanning Mystic River at U.S. Route 1, Groton, Ne...
Significance: The Mystic River Bridge is significant as an example of the Brown Balance Beam Bascule, an innovative design that raised movable-bridge technology to a new level of refinement in the early 20th ce... More
U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela Riv...
See also HAER PA-200 for additional documentation. Includes written data (pages 76 through 94). Significance: As a group, the structures and steel-making equipment from Homestead Works represented one of the na... More
U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela Riv...
See also HAER PA-200 for additional documentation. Includes written data (pages 76 through 94). Significance: As a group, the structures and steel-making equipment from Homestead Works represented one of the na... More
U.S. Steel Homestead Works, Blast Furnace Plant, Along Monongahela Riv...
See also HAER PA-200 for additional documentation. Includes written data (pages 76 through 94). Significance: As a group, the structures and steel-making equipment from Homestead Works represented one of the na... More
Centennial Bridge, Spanning Mississippi River at U.S. Highway 61, Dave...
Significance: This bridge is a major river span and was the first tied-arch span across the Mississippi River. The bridge was fabricated, and the superstructure built, by American Bridge Company, New York, one... More
Monongahela Railroad, New Geneva Bridge, Spanning Monongahela River, S...
Significance: The bridge at New Geneva is significant for its long Petit through through truss, and more importantly, for its erection by end manufacturing. At the time of its construction, it was the longest a... More
U.S. Steel Duquesne Works, West bank of Monongahela River along State ...
Significance: The construction of the Duquesne Steel Works marked an important event in the movement toward integrated steel producing ventures in the Monongahela Valley of western Pennsylvania. Constructed af... More
Charlestown Navy Yard, Shipfitters' Shop, Southeast side of First Aven...
The Boston Redevelopment Authority hired William A. Owens to document all buildings in the Charlestown Navy Yard in 1977, most of which were exterior photographs. Significance: The Charlestown Navy Yard comple... More
Charlestown Navy Yard, Shipfitters' Shop, Southeast side of First Aven...
The Boston Redevelopment Authority hired William A. Owens to document all buildings in the Charlestown Navy Yard in 1977, most of which were exterior photographs. Significance: The Charlestown Navy Yard comple... More
Charlestown Navy Yard, Shipfitters' Shop, Southeast side of First Aven...
The Boston Redevelopment Authority hired William A. Owens to document all buildings in the Charlestown Navy Yard in 1977, most of which were exterior photographs. Significance: The Charlestown Navy Yard comple... More
Williamstown-Marietta Bridge, Spanning Ohio River between Williamstown...
Significance: The Williamstown-Marietta Bridge was the first highway bridge in the United States built in a cantilever fashion over an inland river. In 1902, it was the site of the first strike by the newly-fo... More
Williamstown-Marietta Bridge, Spanning Ohio River between Williamstown...
Significance: The Williamstown-Marietta Bridge was the first highway bridge in the United States built in a cantilever fashion over an inland river. In 1902, it was the site of the first strike by the newly-fo... More
Williamstown-Marietta Bridge, Spanning Ohio River between Williamstown...
Significance: The Williamstown-Marietta Bridge was the first highway bridge in the United States built in a cantilever fashion over an inland river. In 1902, it was the site of the first strike by the newly-fo... More
Williamstown-Marietta Bridge, Spanning Ohio River between Williamstown...
Significance: The Williamstown-Marietta Bridge was the first highway bridge in the United States built in a cantilever fashion over an inland river. In 1902, it was the site of the first strike by the newly-fo... More
Williamstown-Marietta Bridge, Spanning Ohio River between Williamstown...
Significance: The Williamstown-Marietta Bridge was the first highway bridge in the United States built in a cantilever fashion over an inland river. In 1902, it was the site of the first strike by the newly-fo... More
General Dynamics Corporation Shipyard, Wellman-Seaver Crane, 97 Howard...
Significance: Erected in 1901, Structure No. 30S, the Wellman-Seaver Folding Gantry Crane, or Crane S-1, is significant as the oldest and longest-operating crane in the Quincy-Fore River Shipyard. Located on P... More