Requires little skill and has little physical challenge.
Tread is smooth, level, and wide, with generous clearing of trees,
limbs, and other vegetation above and to each side of the trail
to permit easy passage.
Elevation gain or loss is minimal.
Streams are most often crossed with bridges.
Requires a minimal skill level and provides a minimal
physical challenge.
Tread surface contains roots and embedded rocks. Clearing of trees,
limbs, and other vegetation above and to each side of the trail may
result in occasional contact by the users.
Elevation gain or loss is moderate.
Streams are most often crossed by fords.
Requires a high degree of skill and provides a definite physical challenge.
Tread is seldom graded except on steep side slopes for safety and prevention
of soil erosion. Minimal clearing of trees, limbs, and other vegetation
results in hampering the progress of the user.
Elevation gain or loss is usually severe.
Streams are crossed by fording and are sometimes difficult.