Civil

Designed by Claude A. P. Turner, a pioneer of reinforced concrete construction, the Marshall Building was constructed originally in 1906 as a five-story building. In 1911 the sixth floor of the building was added as per Turner's original design. This building is the oldest extant example of…

The granite milestones marking the Mason-Dixon Line bear crests from the two parties involved in the land-grant dispute, the families of William Penn and Charles Calvert (also known as Lord Baltimore). 

What is now generally referred to as the Mason-Dixon Line was established by the…

The Rogue River Bridge was the most advanced concrete bridge in America when it was built. Distinguished bridge engineer Conde McCullough employed the techniques of Frenchman Eugene Freyssinet to create thin, graceful concrete arches for this seven-span structure.

Pre-compression of the…

The city of Shreveport could not justify the cost of building a water distribution system solely for the purpose of supplying potable water. It was a series of disastrous fires in the 1880s that galvanized support for a pumping facility that would provide ample water for firefighting. 

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While the Erie Canal  has become well-known in the annals of American history, the Middlesex Canal, built two decades earlier and a model for canal engineers throughout young America, has only recently become recognized for its important achievements. Extending 27 miles northeast from Boston…

In 1794, Congress authorized and President Thomas Jefferson signed into law the raising of a Corps of Artillerists and Engineers (now the United States Army Corps of Engineers) to be educated and stationed at the newly created United States Military Academy. The U.S. Military Academy was the…

This was America's first large-scale activated sludge plant. The successful operation of Milwaukee's sewage treatment plant led the way for many other American municipalities to adopt its methods of efficient environmental recycling.

Prior to 1925, sewage and industrial waste from the…

Minot's Ledge is a wave-swept rock formation in a rocky area of ocean about a mile off the Cohasset shore near Boston. Numerous serious shipwrecks prompted the government to erect a beacon there, and construction began in the summer of 1847.  

The light, constructed on tall iron…

Known as "the highest and lowest holing in history," the tunnel bored through the Rockies at an elevation of 9,200 feet, 2,800 feet below the surface. Eight hundred men worked around the clock for 3 1/2 years, moving 3 billion pounds of rock. 

Three thousand feet under the Continental…

The Memphis Bridge (now called the Frisco Bridge) comprises three spans across the Mississippi River. With a main span measuring over 790 feet, it was one of the longest railroad bridges in the world upon completion. The renowned George Morison, after whom the bridge is unofficially named,…

Just 20 years after settling the uninhabited Salt Lake valley, Brigham Young and his Mormon followers completed one of the nation's most impressive public structures. The 9,000-seat Mormon Tabernacle boasts a clear span roof measuring 150 feet by 250 feet, its timber trusses joined with wooden…

Designed, patented, and built by Thomas W.H. Moseley, this arched 96-foot span bridge preceded by years the standard use of wrought iron for bridges. For the first time in the United States, Moseley incorporated the use of riveted wrought-iron plates for the triangular-shaped top chord.

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The Mullan Road was designed to facilitate the movement of troops and supplies across the Rocky Mountains between the Missouri River basin in the Great Plains and the Columbia River Basin at the Columbia Plateau during times of Indian hostilities. But because peace was reached with the Northwest…

The National Road was the first interstate highway in the United States, and the first roadway to be financed with federal money. Authorized by Congress during the administration of Thomas Jefferson in 1806, the road was built over time and in sections from Cumberland, Maryland, westward through…

Navajo Bridge spans Marble Canyon, 470 feet above the Colorado River in Grand Canyon National Park. It was considered the highest steel arch bridge in America when completed.

The Navajo Bridge (also known as the Grand Canyon Bridge) was built in 1929 by the Arizona Highway Department and…

In 1794, the Delaware legislature authorized a lottery to fund the erection of ice piers in the harbor at New Castle. The ice harbor was designed to protect anchored ships from storms and ice. At the time, New Castle served as the principal winter port for ships from the Port of Philadelphia…

Norris Dam impounds the Clinch River, a mountain tributary of the Tennessee River. The facility stands as a tribute and symbol of the birth of the Tennessee Valley Authority (TVA). Given broad jurisdiction over resource development in the watershed (a 40,000-square-mile basin comprising parts of…

The Northern Pacific High Line Bridge No. 64, built between 1907 and 1908, has continued to perform yeoman service in the uninterrupted flow of the Nation's commerce. Nearly, 100 years after this bridge officially opened, it still carries 125-ton car unit coal trains, double stack container…

The crossing of the Delaware River at Easton, Pennsylvania, provided a central link in travel from the northeastern seaboard to America's inland territories throughout the 18th and early 19th centuries. From 1806 to the mid-1890s, travelers used a landmark wooden structure built by noted bridge-…

The United States became interested in a water route through the Panamanian isthmus in the mid-1850s, but it was the French who first attempted to build the Panama Canal. Led by Ferdinand de Lesseps, builder of the Suez Canal in Egypt, the French began the project in 1876. Conditions were brutal…