Railroad bridges and train trestles can trace their roots back to the industry's beginnings in the mid-19th century. Prior to the development of iron, and later steel, early bridges were built of either stone or wood. During this time engineers designed some quite stunning, and perhaps somewhat harrowing, wooden bridges that appeared as if they might not hold a person let alone a heavy train. However, after iron and steel began to be widely employed
in the latter 19th century new bridge designs were employed, the most common of these being trusses, beams, girders and spans. Today, many of the stone-arch bridges built in the mid-19th century remain in regular service due to their exceptional construction. Additionally, most are also either on the National Register or National Historic Landmarks with names like the Thomas Viaduct in Maryland or the Starrucca Viaduct in northeastern Pennsylvania.
One of the first railroad bridges to be built in the country is credited to the Baltimore & Ohio Railroad which constructed its Thomas Viaduct in 1835 located at Elkridge, Maryland over the Patapsco River. The bridge gained its name for the B&O's first president, Philip E. Thomas and at the time of its construction was the world's longest masonry bridge and the first curved structure of its kind. Even today it remains the largest bridge of its type and still carries regular freight and passenger trains to this day, a testament to the strength and longevity of not only its stone construction but also the masons who built it.
Ballast, Supporting The Rails And Ties
Coaling Towers, Keeping Steam Locomotives Fueled
Railroad Signals, How They Function
The Track, The Railroad's Highway
The Ties, Supporting The Rails
Tunnels, Conquering The Mountain
The Yards, Sorting And Classifying
The Roundhouse, Once The Realm Of Steam
The Turntable, Turning Locomotives
Wayside Signs, Along The Right-Of-Way
Other famed stone bridges around the country include the Pennsylvania Railroad's Rockville Bridge near Harrisburg, Pennsylvania crossing the mighty Susquehanna River. This massive structure is 3,820 feet long and includes 48 arches. it opened in 1902 and still carries Norfolk Southern Railway freight trains and Amtrak passenger trains today. Although not built of stone it should be noted that one of the most famous arched railroad bridges in the country is the Delaware, Lackawanna & Western Railroad's Tunkhannock Viaduct. Topping out at 240 feet above the valley floor and roughly a half-mile long at 2,375 feet the railroad structure is a striking sight (made all the more impressive by Lackawanna R.R. located across the center arch).
While stone bridges are renowned for their overall beauty and extremely long lifespans they are also very expensive to build. To help keep expenses down early railroads began engineering railroad bridges at first from wood and later from iron once it became available. Some of the earliest engineered railroad bridges included differing truss designs such as the Burr arch truss of 1817 and own lattice truss of 1820. One of the most common early such designs once iron was available was the Pratt truss of 1844, patented by Thomas and Caleb Pratt, and the Warren truss of 1848. These designs can still be found on some railroad lines in the country even today (and some have or are in the process of being preserved).
As steel became available in the late 1800s larger and more impressive railroad bridges were constructed. Virtually all of these were of designs already on the books, simply differing variations of them such as the cantilever truss and through arch design, the latter of which is perhaps most recognized as railroad bridges go in the New York, New Haven & Hartford Railroad's Hell Gate Bridge which connects Queens and Manhattan over the East River. This impressive structure was completed in September 1916 and remains an important artery for Amtrak and freight trains today.
The most common railroad bridges are probably variations of the span plate girder designs. These bridges typically only span small streams, cuts or open areas and are relatively cheap and inexpensive to build. However, even some longer railroad bridges will be partially constructed of the span or girder design, it simply depends on how the engineer has drawn up the plans for a particular structure. For an excellent general overview of common railroad bridge designs please click here.
Railroad bridges will forever be an important component of the railroad infrastructure which allows trains to cross the country because obviously without them we could never have spanned the smallest stream to largest valley. It should also be mentioned that several bridges are nearing the end of their useful lifespan and will need to be replaced soon (or already have been). Obviously, it is necessary that these bridges are rebuilt sooner rather than later not only to keep an accident from happening but also to keep the flow of goods back and forth across the country. So, when state or federal money is being authorized to help in the building of a private, new bridge it is certainly going towards a worthy cause and is not a waste of tax dollars as these structures are very expensive to construct, even for large railroads (several million dollars per bridge is common these days).
Header Photo: Drew Jacksich
A popular pastime for many is studying and/or exploring abandoned rights-of-way. Today, there are tens of thousands of miles scattered throughout the country. Many were pulled up in the 1970's and 1980's although others were removed long before that. If you are researching active or abandoned corridors you might want to check out the United States Geological Survey's (USGS) Historical Topographic Map Explorer. It is an excellent resource with thousands of historic maps on file throughout the country. Just type in a town or city and click on the timeline of maps at the bottom of the page!
You will be hard pressed at finding a better online resource regarding diesel locomotives than Craig Rutherford's TheDieselShop.us. The website contains everything from historic (fallen flags) to contemporary (Class I's, regionals, short lines, and even some museums/tourist lines) rosters, locomotive production information, technical data, all notable models cataloged by the five major builders (American Locomotive, Electro-Motive, General Electric, Fairbanks-Morse, and Baldwin), and much more. A highly recommended database!
In 1998 a gentleman by the name of Andre Kristopans put together a web page highlighting virtually every unit every out-shopped by General Motors' Electro-Motive Division. Alas, in 2013 the site closed by thankfully Don Strack rescued the data and transferred it over to his UtahRails.net site (another fine resource). If you are researching anything EMD related please visit this page first. The information includes original numbers, serials, and order numbers.