You don't have to spend much time with model trains to realize that they come in a number of different sizes. These differences are one of the things that make model trains so much fun because there are advantages to each size. Let's take a look at them so you can think about which size may be best for you.

Z scale: Trains built to a ratio of 1:220. A 75-foot-long locomotive measures 4 inches long. The rails of the track are 6.5 mm apart.

N scale: Trains built to a ratio of 1:160. A 75-foot-long locomotive is 5 1/2 inches long. The rails of the track are spaced 9 mm apart.

HO scale: Trains built to a ratio of 1:87. A 75-foot-long locomotive is 10 1/2 inches long. The rails of the track are 16.5 mm apart.

S scale: Trains built to a ratio of 1:64. A 75-foot-long locomotive is 14 inches long. The rails of S gauge track are 7/8 inches apart.

O scale: Trains built to a ratio of 1:48. A 75-foot-long locomotive is 18 3/4 inches long. The rails of O gauge track are 1 1/4 inches apart.

G scale: These trains are built to a ratio of 1:22.5. A 75-foot-long locomotive is 40 inches long. G and other large scale trains run on gauge 1 track with rails 45 mm apart.

Which size is best? You can see that no one scale is right for everyone. Look at several of them and consider how much space you have to devote to your trains, whether you want to run longer trains amid towering scenery, and how much you can spend on your hobby. Talk with experienced modelers and learn what they like. And don't worry if you change your mind and later decide that a different scale is a better choice for you.

For more information on the hobby of model trains, check out Model Railroader Magazine The world's most popular model railroading magazine.