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”)



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]

Clubs & Associations

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Recent News: HO Scale Model Trains

Source: Google News

Mad City Model Railroad Show & Sale set February 20-21
hngnews.com, February 8th

The 49th annual Mad City Model Railroad Show and Sale -- one of the nation's most wide-ranging model train shows drawing close to 10,000 attendees -- will take place Saturday and Sunday, Feb 20 and 21 at the Alliant Energy Center, Exhibition Hall, in...Read more

Adults are like kids in a candy store at City of Firsts Train Show
Kokomo Tribune, February 6th

The vendors boasted just about anything a train enthusiast would be interested in. The toys included a number of different brands, including Marx, H.O., Z-Gauge and T-Gauge, just to name a few. There were books on the history of trains and books on how...Read more

Live Wire: No free shredding events on the horizon
Fayetteville Observer, February 5th

A: We don't know of an appraiser, but you can do some research on the value of these trains yourself. Do this by searching online auction sites such as eBay for items like those in your father's collection. There are tens of thousands of HO scale model...Read more

Vegas Stripped: Graffiti canvas changes for 'saved' artist — VIDEO
Las Vegas Review-Journal, February 4th

Tom "Cruise" paints a model train at his home in North Las Vegas Wednesday, Feb. 3, 2016. Once homeless in the pacific northwest, he painted real trains and walls, but also painted model trains to make money. Today graffiti on ho-scale trains is...Read more

Model train show returns to Port Hope this weekend
Peterborough Examiner, February 3rd

From left, Ganaraska Railway Modellers Carl Kinzinger, Dave Ellis, Peter Shee, Kent Bartley and Dean Smith welcome you to their 23rd annual Model Train Show this weekend at the Town Park Recreation Centre in Port Hope. CECILIA ... Club member mainly...Read more

The Burlington County Model Railroad Club HO-scale model railroad layout
Burlington County Times, February 2nd

The Burlington County Model Railroad Club opens its HO- scale model railroad layout in the basement of the Footlighters Playhouse, 808 Pomona Road, Cinnaminson, to the public from noon to 5 p.m. Feb. 20 and 21. Free, donations appreciated. For more ...Read more

Young and old get on board for Valley River model train show
The Register-Guard, January 30th

“We're here because we enjoy it, we have fun and we can share the fun with everybody else,” said Gary Schwieger, a board director for the Eugene-based Willamette Cascade Model Railroad Club, which operated a mammoth HO-scale display measuring at ...Read more

Line between kids, adults blurs at N.E. model train show
Cecil Whig, January 11th

Not all of the model train engineers present on Saturday are seasoned hobbyists. North East-area resident Garrett Dorsett, 16, has been adding to his sprawling HO layout for the past 12 years, with the help of his mother, Dawn Dorsett, and his sister...Read more