Railroad Landmarks (USA): Famous Bridges, Tunnels, Passes & Grades

Last revised: August 13, 2026

American railroading is full of places where the map refuses to stay simple—where the line had to climb, loop, tunnel, leap a river, or cut through a mountain to get freight and passengers through. Those spots became the industry’s landmarks: the Baltimore & Ohio’s early Thomas Viaduct, the Erie’s stone Starrucca Viaduct, the nearly five-mile Hoosac Tunnel, the Great Northern’s long Cascade Tunnel, the Pennsy’s Horseshoe Curve, the Southern Pacific’s Tehachapi Loop, and dozens of other bridges, grades, passes, and cutoffs.

Many were finished with hand tools, black powder, and enormous human cost long before modern machinery. A surprising number still carry trains every day; others survive as trails, overlooks, or ruins. This hub introduces how those works were built, why they still matter, and a directory of American-Rails.com landmark profiles—engineering feats and classic railfan locations (stations and depots are covered separately under stations).

On this page: At a glance · What counts as a landmark · Icons of the map · Built by hand · John Henry · Why they still matter · Directory by type · Bridges & viaducts · Tunnels · Grades, curves & loops · Passes & summits · Cutoffs & lines · Related reading

Rio Grande PA-1 6013 Hanging Bridge Royal Gorge Colorado May 21 1967

Rio Grande PA-1 #6013 stopped at the famous Hanging Bridge in Colorado’s Royal Gorge with the Royal Gorge, May 21, 1967. The Arkansas River is at right. Ed Fulcomer photo. American-Rails.com collection.

At a Glance

Topic	Notes
What this hub covers	Major U.S. railroad engineering works and famous line locations: bridges/viaducts, tunnels, mountain passes, steep grades, loops/curves, cutoffs, and selected railfan hot spots
What it does not cover	Passenger stations and depots (see stations); museums as institutions (see museums); individual fallen-flag company histories (see fallen flags)
Typical construction eras	1830s pioneers (e.g., Thomas Viaduct, Staple Bend Tunnel) through early–mid 20th century bores and steel spans (Moffat, Cascade rebuilds, Hell Gate, etc.)
Materials evolution	Stone masonry → iron → steel → concrete; each shift cut cost or increased span/length while changing how landmarks look
Historic recognition	Many sites are ASCE Historic Civil Engineering Landmarks, National Historic Landmarks, or National Register properties—and still host freights or Amtrak
First U.S. railroad tunnel (often cited)	Staple Bend Tunnel near Johnstown, Pa.—Allegheny Portage Railroad; construction 1831–1834
Profiles linked below	About 40 American-Rails.com landmark and location articles (bridges, tunnels, grades, passes, cutoffs, loops)
Living vs. legacy	Many landmarks remain in freight service; others are abandoned, trail-converted, or partially ruined (e.g., Kinzua after storm damage)

What Counts as a “Railroad Landmark” Here?

On this site, a landmark is usually a place where engineering or geography made the railroad memorable—not every milepost and not every small depot. Readers (and search engines) tend to group the same ideas under several everyday phrases:

Famous railroad landmarks / historic railroad sites
Railroad bridges and viaducts
Railroad tunnels
Mountain railroad passes and summit grades
Railfan hot spots (Tehachapi, Horseshoe Curve, Cajon, Sherman Hill, and similar)

Those queries point to one family of places: the spectacular bits of the map. A stone viaduct that still carries coal trains, a five-mile tunnel under a mountain range, a spiral loop that gains elevation without an impossible grade—these are the landmarks. They are also where photographers and railfans still gather, because the railroad is forced into drama instead of straight, flat running.

Railroads themselves recognized the cost of pure stone construction and shifted to iron, steel, and later concrete for many large works. The best early masonry projects—Thomas, Starrucca, and peers—were so well built that they outlasted the companies that ordered them and still appear on modern operating maps.

Icons of the Map (If You Only Know a Few Names)

Most visitors to this hub arrive knowing one famous place and wanting the rest of the map. These are among the names that dominate both railfan conversation and general “what should I see?” lists—each has a full profile linked in the directory below.

Landmark	Why it is famous	Profile
Horseshoe Curve (Pa.)	PRR’s Allegheny crossing; still a premier railfan overlook on the former Pennsy main	Horseshoe Curve
Tehachapi Loop (Calif.)	SP spiral that gains elevation without an impossible grade; among the most photographed freights in the West	Tehachapi Loop
Hoosac Tunnel (Mass.)	Nearly five-mile bore; long the longest railroad tunnel in the U.S. and a legendary construction ordeal	Hoosac Tunnel
Starrucca Viaduct (Pa.)	Stone-arch masterpiece of the Erie era; still carries trains and often cited as ASCE historic landmark	Starrucca Viaduct
Thomas Viaduct (Md.)	Early B&O multi-arch stone bridge; pioneer engineering still in the operating plant	Thomas Viaduct
Moffat Tunnel (Colo.)	Continental Divide bore that reshaped Denver–West access; still a key UP mountain passage	Moffat Tunnel
Cascade Tunnel (Wash.)	Great Northern mountain solution in the Cascades; successor BNSF still depends on the alignment family	Cascade Tunnel
Sherman Hill (Wyo.)	Classic UP Overland summit district; helper and high-horsepower country in steam and diesel eras	Sherman Hill
Donner Pass (Calif.)	Central Pacific / SP Sierra crossing; snow, snowsheds, and transcontinental lore	Donner Pass
Hell Gate Bridge (N.Y.)	Steel arch into New York; still a critical passenger/freight approach span	Hell Gate Bridge
Saluda Grade (N.C.)	Among the steepest mainline grades in the East; operating legend even after freights left the hill	Saluda Grade
Key West Extension (Fla.)	Flagler’s overseas railroad—bridges over open water, hurricane drama, partial trail rebirth	Key West Extension

From those anchors, the directory spreads into less-publicized but equally important works: cutoffs that shortened main lines, southern and western helper districts, stone viaducts that never made the postcard rack, and junctions like the Richmond Triple Crossing where geography and corporate ambition stacked three levels of track.

Built by Hand: Labor, Danger & How the Landmarks Were Made

It is hard, from a world of diesel excavators and laser surveys, to picture how 19th-century rail lines were forced through mountains and across rivers. There was little heavy machinery at first, no modern OSHA regime, and no easy escape from weather. Put bluntly, construction was not for the weak.

Jeffrey Marcos Garcilazo, in Traqueros: Mexican Railroad Workers in the United States, 1870–1930, notes that track workers were injured so often that “space does not allow for the discussion of the wide variety and conditions under which these accidents occurred.” An entire bookshelf could be devoted to that subject alone. The men who built the landmarks came from many backgrounds—Irish and other European immigrants in the East, Chinese labor on much of the Central Pacific’s Sierra work, African American crews (including the steel drivers of southern tunnel lore), Mexican traqueros and their families (sometimes living in converted boxcars), and, in the antebellum South, enslaved labor on some projects.

Tunneling was among the worst work. The first railroad tunnel commonly credited in the United States is the Staple Bend Tunnel near Johnstown, Pennsylvania, built for the Allegheny Portage Railroad beginning in 1831 and completed in 1834. With no mechanization, crews used picks, shovels, and unstable black powder, “eyeballing” alignment in conditions that killed and maimed. Later bores such as Hoosac in Massachusetts and the Sierra tunnels of the Central Pacific became notorious for the same mix of geology, explosives, and poor ventilation. Dynamite and power drills improved the tools; they did not make the work gentle.

Surveyors shared the hardship in a different way. From the 1830s projects through the Transcontinental routes west of the Mississippi, corridors were laid out on horseback and on foot, often without wagon roads. The editors of American Heritage’s Railroads in the Days of Steam include a well-known image of surveyors scaling rock in the Uinta country of Utah on Central Pacific work. In parts of the West, construction and survey parties also faced conflict with Native nations whose lands and buffalo herds were disrupted by the advancing railhead; the federal government sometimes provided military escorts numbering from small detachments to parties of a hundred men—protection that was imperfect.

When we admire the finished landmarks—the arches of Starrucca or Thomas, the bore of Cascade or Moffat, the geometry of Tehachapi—we are looking at engineering directed by surveyors and civil engineers and realized by thousands of workers whose names almost never appear on dedication plaques. Both sides of that story belong in any honest landmark history.

Southern Pacific Cotton Belt SD45T-2 9391 Tehachapi Loop Walong California

Southern Pacific / Cotton Belt SD45T-2 #9391 leads an eastbound over the loop on Tehachapi at Walong, California. Mike Bledsoe photo. American-Rails.com collection.

John Henry and the Big Bend Tunnel

No piece of American railroad labor folklore is more famous than John Henry, the steel-driving man associated with construction of the Chesapeake & Ohio’s Big Bend Tunnel near Talcott, West Virginia. In the legend, Henry races a steam drill, wins, and dies with his hammer in his hand. Historians still debate how much of the tale is biography and how much is ballad—but the song preserved a truth every tunnel crew understood: human muscle was pitted against new machines in deadly rock, and the cost of winning a day’s progress could be a life.

A few lines from the traditional piece capture the tone:

John Henry was a railroad man,
He worked from six ’till five,
“Raise ’em up bullies and let ’em drop down,
I’ll beat you to the bottom or die.”

John Henry said to his captain:
“You are nothing but a common man,
Before that steam drill shall beat me down,
I’ll die with my hammer in my hand.”

For more on C&O mountain railroading and related West Virginia grades, see profiles such as Cranberry Grade and the broader railroad history hub.

Why Railroad Landmarks Still Matter

Unlike many 19th-century factories that survive only as ruins or museums, a remarkable number of great railroad works remain operationally critical. Trains still climb Horseshoe Curve, spiral through the Tehachapi Loop, and use the Cascade and Moffat tunnels. Hell Gate Bridge still feeds passenger and freight moves into New York. Older masonry such as Starrucca and Thomas continues in service on successor railroads. Visitors at a public overlook are not only looking at history; they are watching a modern supply chain use infrastructure designed in the steam age.

That continuity is rare in industrial America. Rights-of-way through difficult terrain are hard to replace, and the original alignments were often the best available paths. Landmarks also concentrate drama: railroads are mostly linear and repetitive, so the places where the line must bend, climb, or leap become magnets for railfans and photographers generations after opening day.

Finally, these sites embody a particular American story—the willingness to spend money, labor, and ingenuity to force transportation through hard country. In an age of interstates and air travel, the permanence of the old railroad works remains impressive. They are among the most durable, still-functional monuments of the industrial era. Some locations, sadly, are gone or no longer used as built (storm-damaged viaducts, abandoned summits, trail conversions); even those remnants show what the industry once dared to build.

Union Pacific DDA40X 6927 SD40-2 3197 Sherman Hill Wyoming circa 1985

Union Pacific DDA40X #6927 and SD40-2 #3197 lead a westbound over Sherman Hill, Wyoming, circa 1985. Mike Bledsoe photo. American-Rails.com collection.

Landmark Directory (American-Rails.com Profiles)

Jump to detailed articles by type. The same list is what the original hub collected as a flat A–Z set; grouping by bridge, tunnel, grade/loop, pass, and cutoff matches how people actually browse and search.

Bridges & Viaducts

Hell Gate Bridge
Keystone Viaduct
Kinzua Viaduct
Newark Bay Bridge
Poughkeepsie Bridge
Rockville Bridge
Salisbury Viaduct
Starrucca Viaduct
Thomas Viaduct
Tulip Viaduct
Tunkhannock Viaduct
Key West Extension (overseas railroad / bridges over water)

Tunnels

Grades, Curves & Loops

Mountain Passes & Summits

Cutoffs, Wyes & Special Alignments

Type	What readers usually want	Classic examples on this site
Viaduct / bridge	Span length, builder, still in use?	Thomas, Starrucca, Tunkhannock, Rockville, Hell Gate
Tunnel	Length, railroad, construction drama	Hoosac, Cascade, Moffat, Snoqualmie
Grade / curve / loop	Percent grade, helper districts, photos	Horseshoe Curve, Tehachapi, Saluda, Sand Patch, Clinchfield Loops
Pass / summit	Elevation, winter operations, railroad	Donner, Cajon, Sherman, Raton, Stampede, Tennessee
Cutoff	Why built, what it bypassed	Lucin, Lackawanna, Magnolia, Patterson Creek

Railroad history · Fallen flags · Tycoons
Steam locomotives · Diesel locomotives · Locomotive history
Stations and depots · Museums · Tourist trains
Rail infrastructure · State history · Home

Sources

Garcilazo, Jeffrey Marcos. Traqueros: Mexican Railroad Workers in the United States, 1870–1930. Denton: University of North Texas Press (and related editions)—labor conditions context
Editors of American Heritage. Railroads in the Days of Steam—survey and construction imagery/context
ASCE Historic Civil Engineering Landmark designations and railroad engineering secondary literature for individual bridges and tunnels
John Henry / Big Bend Tunnel folk history and C&O construction tradition (legend vs. documentary record remains debated)
American-Rails.com individual landmark profile pages linked in the directory above
Operating practice and railfan literature on living landmarks (Horseshoe Curve, Tehachapi, Moffat, Cascade, major western passes)

Landmarks hub revised August 2026 (clearer title and scope, anchors, glance and type tables, categorized profile directory, MailChimp stub, lead text before hero image) while retaining core research on hand-built construction, immigrant and minority labor, Staple Bend Tunnel, John Henry, materials evolution, and the idea that many great works still carry trains.