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

Other Great Reference Sites

Most watched eBay auctions    

Herpa Athearn Boley Kibri Up Cn Utilitytruck Set #2 Rps Ford Crane Mow Ho 1/87 Victorian Railways Brass Ho R ClassHo Brass Sunset Sp Southern Pacific Whale Back Tender OnlyVntg United Brass Ho Vulcan Duplex Locomotive Pfm Japanese Import Train W/ BoxTenshodo 126 Brass Up 4-8-8-4 Big Boy Steam Locomotive & Tender Ex/boxHo Brass Sunset Sp Southern Pacific C-19 Tender OnlyHo Scale Junk Box #104: Steam Locomotives Ho 1:87 Set Of 5 Burlington Northern Bn Twin-pack Intermodal Container CarsVntg United Brass Ho Climax Logging Locomotive Pfm Japanese Import Train Ho 1:87 Atlas Norfolk Southern Ns C40-9 LocoBroadway Limited 4-8-8-2 Southern Pacific Cab Forward SoundTw Custom Union Pacific Chevy 'rip Track' Wheel Truck Ho 1:87Ho Brass Sunset Sp Southern Pacific 2-8-0 Unpainted Engine OnlyFujiyama Ho Scale Brass Northern Pacific Class Z.5 2-8-8-4 Steam Locomotive & TeRt Kato #30-9017 Gunderson Maxi Iv Double Stack Car Ttx 732170 1:87 HoHo 1:87 Hon30 Minitrains Set 0-4-0 Steam Loco & 8 Cars Coal Cars, Mine Cars NewDjh Nsw Ad60 Class Beyer Garratt Loco RtrLima Ho Nsw C3830 Steam LocomotiveHo 1:87 Hon30 Minitrains 0-4-0 Steam Locomotive Island Creek Coal Co. New In BoxHo Scale Athearn Mkt Sd40-2 Powered Locomotive 616 W/dcc Quick-plug Equipped Lloyds Ho Nsw 620/720 Class Railmotor Set - Candy - RtrBrass Ho Scale Emd Sdl39 Milwaukee Road / Cmstp&p Unpainted Omi-5119 Excellent!Mth Ho New York Central 4-6-4 Dreyfuss Dcc And SoundHo-brass Custom Brass New Haven R-3a 4-8-2 Steam LocomotiveHerpa Boley International Utilitytruck Set #1 Rps Ford Crane Mow Ho 1/87 United Models Ho Brass Class "b" 2-truck Shay/boxBroadway Limited Prr I 1 Sa 2-10-0 Steam Locomotive & Tender Paragon SeriesHo 1:87 Hon30 Minitrains 0-4-0 Steam Locomotive Union Rr Co. New In BoxWestside Model Co. Ho Brass Virginian Triplex 2-8-8-8-4 Steam Locomotive/boxAustrains Nsw 80 Class €Pfm Ho Scale Brass Frisco 4-8-2 Steam Locomotive & Tender Ex/boxUnited Models Ho Brass Climax Geared Locomotive Ex/box*tenshodo ~ Tender For Great Northern 2-8-0 Steam Locomotive ~ Brass ~ Ho ScaleHo 1:87 Atlas Silver Series Csx Dash 8-40cw Diesel Locomotive, No Number1:87 Ho Athearn Kenworth W-900 Custom Log Truck Herpa TrailerAtlas #9641 Ho Scale Conrail #6082 Dash 8-40cw W\\qsi Ver7 Sound And DccRivarossi 2-8-8-2 At&sf Steam Locomotive W/ #2197 Tender Ho ScaleBachmann Ho Northern 4-8-4 Steam Engine Locomotive W/ Tender 8601 Cb&q Smoke ExcHo 1:87 Hon30 Minitrains 0-4-0 Steam Locomotive Undecorated New In BoxHo-brass Custom Brass New Haven 2-10-2 Class L-1 W/side Mounted PumpsBrass - Chesapeake & Ohio / 2-6-6-6 - Class H-8 - AlleghanyImperial Im-103 Ho Brass Prr Class Q2 Dulex 4-4-6-4 Steam Loco & Tender Ex/boxHo-brass Hallmark Rdc-3 Original "budd Car"Scarce 1961 Lionel Ho 0961 Lighted Snap-on Bumpers, Ln/obOverland Models Inc. Omi 3313.1 At&sf B&m Jordan Spreader Factory Painted BlackHo 1:87 Broadway Limited Dcc And Sound L&n J-4 2-8-2 #1776 Steam LocomotiveOmi Union Pacific Coal Turbine Undec. W/decals, Super Rare!!! The Original 80Nwsl Brass Ho Scale Northern Pacific Np 2-8-2 Class W-5Ho Scale Old Time Civil War 4-4-0 Locomotive Decorated For Usmrr-nice Details!!United/pfm Brass Hon3 Scale 2 Truck Shay Ho Brass Sunset Nw Norfolk & Western M 4-8-0 Factory Painted #374Broadway Ltd. Hybrid Ho New York Central 4-6-4 Dreyfuss Dcc/dc And SoundPowerline Ho Nr Bl Class De LocoRivarossi Union Pacific Fef-3 4-8-4 #838 Up New In Box Ho Rr Us 18 Vintage Lima Carrigaes & EngineVintage Roundhouse Southern Pacific 2-8-0 Engine Kit Ho ScaleAthearn Ho Bnsf C44-9w #986 Power Diesel Locomotive* Tenshodo ~ Great Northern 2-6-8-0 Steam Locomotive #1981 ~ Brass ~ Ho ScaleBrass Prr K4s, Pfm - Last Run Of 1980Walthers Proto 1000 Ho Scale Train Rock Island Dl-109 #622 Excellent Condition

Recent News: HO Scale Model Trains

Source: Google News

Movie Capsules: What's Showing
Memphis Commercial Appeal, July 21st

HHH½ Set in the year 2031 aboard the “rattling ark” of a high-tech train that is the cramped home of “humanity's last survivors,” the first English-language feature from South Korea's Bong Joon-ho — director of the 2006 monster masterpiece, “The Host...Read more

Model recalls special rail service to Camp Nakanawa
Crossville Chronicle, July 21st

Over the years, as campers would return to the camp season after season, the train trip became a big reunion with the girls moving from car to car to meet old friends, sing and have a good time. The only bad time on the train was going home when the...Read more

Senior News: July 21 — July 27
Milford Mirror, July 20th

Call for information on other tours including Colorado Rockies and Train Tour Sept. 5-13; Spain and Portugal River Cruise Oct. 3; Reflections of Italy ... The HO scale of model railroading will be used. Donations of any model railroading equipment or...Read more

Backyard transformed into railroad village
Pilot Tribune, July 18th

"I still have my original collection and my other HO model train set at property that I still own in Alta," Peterson said. "From there I started to move on to the bigger stuff and eventually made the jump from HO scale to G scale trains." The scale of...Read more

Model Railroad Group Expanding Train Displays
CBS Local, July 11th

An HO-scale model that's 20 by 40 feet is inside the building. The permanent display is known as the Cooper Park & Eastern Railroad, a fictional railroad set in the 1960s. The layout includes 212 feet of track and more than six trains can run at the...Read more

Kalamazoo Model Railroad Historical Society expanding headquarters, train ...
Mlive Kalamazoo, July 11th

The refurbished caboose sits on a short line of track, surrounded by fully-functional crossing lights and alarms – a real-life example of the massive 20 foot by 40 foot HO-scale model railroad that takes up much of the space within the building. "We...Read more

Model Train Exhibit at Tellus Science Museum
Stephen Burge, July 10th

Members of the Central Georgia Model Railroad Club in Macon built these sets from scratch for an exhibition at Hartsfield-Jackson International Airport. It became so popular that this HO scale model train exhibit has toured several of Georgia's museums...Read more

New train exhibit at Oil Museum
Petrolia Topic, July 8th

“A train of oil hauling vehicles which represents the historical progression in the development of such cars is being built up one car at a time.” The display models are HO scale (HO scale model trains are 1/87th the size of a real train) and the...Read more