Viaduct

The bridge is 408 meters long and weighed approximately 1,500 metric tons when built. Originally supported by four columns, two more were added in later years to support the weight of heavier rail cars.

This majestic viaduct was built during the golden age of railroading. It was at the western end of a major readjustment in grade and alignment of the Erie-Lackawanna Railroad, and had double tracks to carry the trains across the valley of Tunkhannock Creek. The Hallstead cutoff (between Scranton, Pennsylvania and Hallstead, New Jersey) reduced passenger travel time by 20 minutes, and freight travel time by over an hour.

The Triborough Bridge Project is a three-branched waterway crossing that connects Manhattan, the Bronx, and Queens at a junction of the East River and the Harlem River in New York City. The complex structure includes a suspension bridge from Wards Island to Queens, a vertical lift span from Randall's Island to Manhattan, a fixed span (designed to be convertible to a lift span) across the Bronx Kills, viaducts, and an innovative three-legged roadway interchange.

The Starrucca Viaduct of the Erie Railroad Company crosses Starrucca Creek in Lanesboro, Pennsylvania. It is one of the oldest and one of the longest railroad bridges in Pennsylvania. Its 18 slender, semicircular stone arches each span 50 feet and the structure rises 110 feet above the creek.

The workforce consisted of less than 100 men, yet they finished construction in just 94 days. Such speed was possible due to the elimination of scaffolding. Instead, iron rods were used to support construction of the trusses between the towers, and workers moved back and forth across the rods. A dangerous venture, yet no workers were seriously injured.

The Carrollton Viaduct over Gwynn's Falls was the first masonry railroad viaduct constructed in the United States. This structure proved the feasibility of using a viaduct to transport railway vehicles across wide and deep valleys.

For more than 174 years, the Canton Viaduct has stood as a dominating structure on the New England landscape. When completed in 1835, the slightly curved, granite masonry bridge - 615 feet long, 70 feet high, and 22 feet wide - carried a single track of the Boston and Providence Railroad, providing a critical link in the establishment of rail service between Boston and New York. In 1860, a second track was added. With few major alterations, the viaduct has continued to provide safe rail transportation to heavier and faster loads throughout the 20th century.