Using a Hiking Trail Difficulty Rating System
Nearly 59 million Americans hiked at least once in 2021. This is an increase of nearly 10 million since 2019. As more hikers hit trails throughout the United States, hikers may wonder which trails present fitting challenges and which are beyond their skill sets. Taking on a trail with endurance or technical demands that pushes hikers too far is a common reason for injuries.
Unlike the color and shape system used to rate the difficulty of ski trails or the American Whitewater Association international scale of river difficulty, no universally recognized rating system notifies hikers of a trail’s challenge level.
Shenandoah National Park in Virginia maintains a difficulty rating system for the nearly 520 miles of trails in the park. Hiking parties should learn the rating system and assess each trail’s challenge before continuing. The Shenandoah National Park system is unique, with difficulty ratings derived from a formula. The formula determines difficulty by multiplying a trail’s total elevation gain by two, then multiplying the result by the trail’s length in miles. The square root of this result is the trail’s difficulty rating.
For example, a 12-mile hike with a 1,800 foot shift in elevation is rated by multiplying 1,800 by 2 (3,600), multiplying that by 12 (43,200), and finally taking the square root for a trail rating of 207.84. The Shenandoah National Park team simplifies trail ratings by attaching numerical values to one of five challenge levels: easiest, moderate, moderately strenuous, and very strenuous.
Easy hikes have a challenge rating of less than 50. They typically are no more than three miles and feature little in elevation change. Moderate trails are rated 50 to 100, while moderately strenuous and strenuous span 100 to 200. Very strenuous trails are rated 200 or higher. These trails should be attempted only by experienced, prepared hikers.
The Shenandoah National Park system is not always an effective approach to a rating. For example, a 10-mile trail with only 20 feet in elevation gain would be rated 20. While such a trail may not present much of a technical challenge, the average hiker is unlikely to classify a 10-mile, multi-hour hike as easy. Using Shenandoah’s estimates for average hiking pace, an easy 10-mile trail would take the average hiker 15 hours to complete, likely necessitating an overnight stay in the park, hardly an ideal experience for beginners.
If hikers do not feel this formula is effective, they can consider the AMC Western Massachusetts Hike Rating System, which gauges length, pace, and terrain, or the Yosemite Decimal System (YDS). The YDS is similar to the Shenandoah National Park system, consisting of numerical ratings corresponding to escalating trail difficulty levels. Trails are broken down into classes ranging from Class 1 to Class 5, with various intermediate points.
According to the YDS, Class 1 trails are suited to walking, cycling, and casual hikes along well-established trails or even a sidewalk. Class 5 trails, meanwhile, demand technical climbing maneuvers to advance along completely vertical climbs, in addition to increased exposure to the elements. Serious injury or death is likely following a fall during a Class 5 hike.
