Standard gauge was favored for railway construction in the United States, although a fairly large narrow-gauge system developed in the Rocky Mountains of Colorado and Utah.
Outside Colorado, these isolated lines evolved into regional narrow-gauge systems in Maine, New York, Pennsylvania, Ohio, Iowa, Hawaii, and Alaska.
In addition to hauling timber, agricultural products and slate, the Maine lines also offered passenger services.
Narrow gauges also operated in the mountains of New Hampshire, on the islands of Nantucket and Martha's Vineyard and in a variety of other locations.
Purchased for scrap by the Kovalchick Corporation when it ended common carrier service in 1956, it reopened as a tourist railroad in 1960.
The largest concentration was in the Big Level region around Bradford, Pennsylvania, from which lines radiated towards Pittsburgh and into New York state.
The hub of this system, Delphos, Ohio, shared with Durango, Colorado the distinction of being the only towns in the United States from which it was possible to travel by narrow gauge in all four compass directions.
This system was widened to standard gauge on June 29, 1902 and merged with the Chicago, Burlington and Quincy Railroad a year later.
[4] At its peak, the mountain west region had a narrow gauge system which stretched from Montana to New Mexico; with the majority of routes operating out of central hubs in Colorado and Utah.
The railroad's founder William Jackson Palmer during the early planning stages of the railroad in 1871 visited the Ffestiniog Railway in Wales while on his honeymoon, and while in the United Kingdom consulted with Scottish engineer Robert Francis Fairlie who convinced Palmer of the advantages of building the Rio Grande using narrow gauge.
[5] The Rio Grande effectively circled the state of Colorado, and feeder lines were run to the mining communities of Leadville, Aspen, Cripple Creek, Telluride and Silverton.
The Rio Grande would find itself in a railroad war with the Atchison, Topeka and Santa Fe Railway in 1878 from 1880 for control over the Royal Gorge canyon.
Through affiliated companies, the Rio Grande's lines would extended west to Ogden, Utah and south to Santa Fe, New Mexico.
[8] The cash strapped Rio Grande Southern would build a fleet of Galloping Goose cars to preserve the mail contract along their route from the 1930's until the lines abandonment in 1952.
[9] As remaining segments of the Denver & Rio Grande Western's narrow gauge system were abandoned through-out Colorado in the mid-20th century, the San Juan Extension experienced a reprieve with the petroleum industry booming from the 1950's into the 1960's around Farmington, New Mexico.
Operations of the Durango & Silverton and the Cumbres & Toltec have both been impacted by the ongoing Southwestern North American megadrought and fuel availability.
An 1870 article published by the Deseret News reported on the international success of the Ffestiniog and promoted narrow gauge as viable for the Utah territory.
[21] The Utah and Northern Railway connected the fertile Mormon Corridor with the mining camps near Butte, Montana with an extensive three-foot gauge system that lasted from 1871 until 1887.
[22] John Willard Young was a primary investor and owner of many of the territory's narrow gauge lines including the early Utah Northern; and competed with the established standard gauge Union Pacific Railroad and Central Pacific Railroad routes in the region.
Union Pacific made use of Ramsey car transfers through-out Utah and Idaho to account for gauge changes in the region.
[29] The surviving pockets of narrow gauge in the Wasatch Front continued until the Oregon Short Line Railroad built a standard gauge route through Bauer, Utah in 1903; and the Little Cottonwood Transportation Co. (which operated leased track from the Rio Grande on the former Wasatch & Jordan Valley) ended service in 1925.
Some projects would have connected the Nevada narrow gauge network to the lines in Utah & Colorado, such as early projections for the Salt Lake, Sevier Valley & Pioche Railroad which would have connected with other narrow gauge lines at Pioche, Nevada; however none of these railroads were successful in reaching their initial goals.
The Carson and Colorado had been built in 1880 by the Virginia and Truckee Railroad who as traffic was waning from the Comstock Lode, sought to tap into mining claims in California.
[35] Carson & Colorado would become part of the Southern Pacific in 1900, and narrow gauge would be operated as the Keeler Branch by the company until being fully abandoned in 1960.
There were also numerous narrow-gauge logging railroads in Pennsylvania and West Virginia who operated mostly with geared locomotives such as Shays, Climaxes, and Heislers.
Although most of these lines closed by the 1950s, one notable later survivor was West Side Lumber Company railway which continued using 3 ft (914 mm) gauge geared steam locomotives until 1968.
Note: this list intentionally excludes tourist railroads, amusement parks, loggers, and other non-common carriers.
Many pieces of the D&RGW's narrow-gauge equipment were sold off to various other companies upon its abandonment; the Ghost Town & Calico Railroad, a heritage railroad at Knott's Berry Farm in California, operates passenger service daily with two Class C-19 Consolidation (2-8-0) locomotives hauling preserved coaches along with a famed Galloping Goose RGS #3.
On Maui, the Lahaina, Kaanapali and Pacific Railroad operates on 6 miles of tracks through former sugar plantation land.