HO scale model trains are 1/87 the size of real trains and 1/2 the size of O scale model trains (HO stands for "half O"). As with O scale trains, the letter "O" in HO is a misnomer since the designation was initially conceived as a zero to identify trains that were smaller in scale than 1. But the use of the letter O rather than the numeral 0 crept into everyday speech among model-train buffs and remains the standard way to refer to HO scale today.

Though first invented in the 1930s, HO scale model trains didn’t become popular in the U.S. and Europe until the 1950s when the scale was heavily promoted by Märklin, Lionel, Athearn, and others. HO never quite gained acceptance in England, though, where larger 00 scale trains still predominate.

HO has two important benefits over trains of larger sizes. First, an HO scale layout of reasonably ambitious detail and complexity can fit on a table rather than requiring an entire room, as is the case with larger scales. Second, HO trains are less expensive to manufacture than OO, O, and other large-scale trains, which makes them more affordable to collectors and enthusiasts alike.

Most HO scale trains run on two-rail tracks using direct current (DC). Adjusting the voltage delivered to the tracks can increase or decrease the speed of the trains; reversing the polarity causes the trains to roll in reverse. Some manufacturers, notably Märklin, produce HO scale trains that operate on alternating current (AC), which is delivered to the train via a conductive third rail.

The gauge used by the majority of HO scale model trains is a standard HO gauge track that’s roughly proportional to the size of the trains running on top of it. But as with the OO scale trains in England that run on HO gauge tracks, HO scale trains are also made to run on a variety of different gauge tracks, which themselves are scaled-down versions of historical railroad track sizes.

Of these variants, the most common is called HOn3. This code denotes an HO scale train running on a track similar to the 3-foot, narrow gauge tracks used by Rocky Mountain railroad operators in the late 19th century.

One of the most enjoyable aspects of HO for collectors is the opportunity to join a local module club. Members of such clubs build modules of predetermined size; each module has a finite length of track. When members get together at model train exhibitions or in private homes, the modules are linked up and trains are run on the resulting massive layout, which often feels like more than just the sum of its parts.


Best of the Web (“Hall of Fame”)

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HOseeker.net

This site is a treasure trove of HO scale model railroad manufacturer catalogs and other reference information, inv… [read review or visit site]

Airfix Model Railways

Airfix Model Railways

Dave McCarthy's Airfix Model Railway treasure trove is an in-depth archive of the company's plastic railway kits fr… [read review or visit site]

Gateway NMRA

Gateway NMRA

This great reference site for model railroaders, from the Gateway (St. Louis) division of the NMRA (National Model … [read review or visit site]

Postwar Lionel Trains Library

Postwar Lionel Trains Library

Bernie Schulz’s Lionel Trains Library focuses exclusively on postwar Lionel trains and accessories. The site cont… [read review or visit site]

Eric's Trains

Eric's Trains

Eric Siegel's site displays his collection of O-gauge/O-scale trains, tracks, turntables, and other accessories. A … [read review or visit site]

Tech Model Railroad Club of MIT

Tech Model Railroad Club of MIT

MIT's model railroad club, as one might expect, has one of the best websites for learning about how people play wit… [read review or visit site]



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Recent News: HO Scale Model Trains

Source: Google News

Mini trains pull into downtown
Greenville News, August 28th

What's inside is the result of more than four years of labor to bring a miniature train and transportation museum to Greenville, Ruby said, adding that he's fundraised for years to make the attraction a reality. It officially opened its doors to the...Read more

Train Days returns to Los Altos: Museum highlights model railroading
Los Altos Town Crier, August 27th

Participants include the Live Steamers from the Bay Area Garden Railway Society (G scale); the Diablo Pacific Short Line (G scale); the Golden Gate Lionel Railroad Club (O scale); a private collector's Swiss Narrow Gauge (HO scale); Peninsula NTrak and ...Read more

Connellsville walkers get dose of railroad talk, tracing trains' track
Tribune-Review, August 25th

The crowds were then directed to the Connellsville Canteen, where Sechler provided a tour and information on the HO gauge model railroad, built by Harry Clark, a carpenter. Sechler said the display had been headquartered at Nemacolin Woodlands in ...Read more

Train club to hold Wm. Crooks Day event Aug. 30th
Northland Press, August 25th

The Wm Crooks Day event will include a presentation by the man who built the scale model, Robert Victor Wilde; and a short presentation by the President of the train club, providing information about the club. The Last Generation Band will play music...Read more

Model display: Little trains, big attraction
Salisbury Post, August 23rd

There's a “wide gamut” of merchandise, according to Leah Cook, a staff member at the museum who helped organize the train show. Vendors carried model train and layout pieces in all sizes — Z, N, HO, O and G scale. “The model boats are one of the most ...Read more

Marion mayor to give presentation at train show
McDowell News, August 21st

Historic Spencer Shops will hold its railroad show Saturday and Sunday. It will feature train rides across the sprawling railroad complex, including the caboose train. There will also be a dozen model railroad layouts featuring Z, N, HO, O and G scales...Read more

VIDEO: Sun City neighbors have passion for large-scale model trains
Bluffton Today, August 12th

Sun City resident George Rumpp and his neighbor Terry Whalen are working to bring model train aficionados together in a community group called the G-Gauge Modelers. ... “The model railroad club already here specializes in HO gauge,” Rumpp said...Read more

Model train exhibit at Seminole library
Tampa Bay Newspapers, August 11th

SEMINOLE – Model trains, Thomas the Tank Engine, and more will be on exhibit at the Seminole Community Library at St. Petersburg College, 9200 113th St. N. Exhibit hours will be Friday, Aug. 15, 9 a.m. to 6 p.m.; Saturday, Aug. 16, 10 a.m. to 5 p.m...Read more