This is an excerpt from Where the Road Ends by Meghan Hicks & Bryon Powell.
Trail races come in many shapes and sizes. Races of any distance exist, from a few miles to 100 miles (160 km) or more. Many trail events host races of several distances as well, such as a 5 km (3.1 miles), half marathon, and marathon, all offered from the same starting line. You will also find that trail races take place on a variety of surfaces, from the grass of a local high-school cross-country course to up, down, and around some of the world's most imposing mountains.
You'll also have to choose the size of race you wish to participate in, from a small one with 40 or 60 participants to those with thousands of runners. Although you'll find very big races in Europe, the latter is still quite uncommon in North America, at least for now. That said, trail running is growing quickly in popularity, and an evolving race scene is surely part of that.
A trail race in proximity to your home or at an inspiring destination may also factor into your decision. Because of other life commitments, some trail runners desire races that are close to home. Others like to use a trail race as a getaway or a reason to go on vacation. A trail race can make a lovely excuse to explore new places both near and far.
Some communities frequently host trail races, as often as every weekend, whereas other areas with less developed trail running communities might have trail races only a couple times per year. Thus, the actual existence of trail races might help you make the decision about which race you will run. If you live in a place that becomes snowbound in the winter, you will notice that the trail racing scene tapers off when the snow flies.
To find trail races, check out your local running store, ask other runners, search one of the many online trail race calendars, or search online for trail races in a particular geographic area. After you discover your desired race, note the registration procedure. Some small trail races allow you to sign up on the day of the race, but the most popular races may require you to qualify, sign up far in advance, or enter a lottery that determines who can race.
If you want to run a race, check its registration procedure. As trail running increases in popularity, some races require participation in lotteries and sign-ups months in advance.