Trails can easily be classified as Easy, Medium, or Difficult for adaptive riders, but can be difficult to assign a definitive classification because of the numerous factors that determine rideability. For example, a trail can be very easy for any novice rider except for one off-camber section or one obstacle.

Similar in concept to the Yosemite Decimal System

Our rating system has two stages: (1) a general classification and (2) specific subdivisions.

General Rating

A1: Easy (Green)
A2: Intermediate (Blue)
A3: Difficult (Black)
A4: Extreme (Red)

The general rating is determined by the minimum point value of each subdivision below, then assigned a secondary rating based on the total points.

Specific Factors:  


Wide (> 30″) – 0 points
Narrow (< 30″) – 1 point

A1: 0
A2-A4: 1


e.g., pitch, running slope

P1: Easy 0-5º – 0 point
P2: Intermediate 6-10º – 1 point
P3: Difficult 11-20º – 2 points
P4: Extreme 21º+ – 3 points

A1: 0
A2-A4: 1-4

Cross Slope:

e.g., camber

C1: Easy 0-5º / 0-3″
C2: Intermediate: 6-10º / 4-6″ ?
C3: Medium: 10-15º / 7-8″ ?
C4: Difficult: 15-20º / 9-11″ ?
C5: Extreme: 20-25º / 12-14″ ?

A1: 0
A2-A4: 1-4



S1: Paved/Solid
S2: Hardpack dirt
S3: Loose/sandy
S4: Bumpy: small rocks/roots
S5: Rocky

A1: 0
A2-A4: 1-4


O1: None
O2: Mild: gravel, small roots
O3: Moderate: fixed or loose objects likely
O4: Technical: larger objects difficult to get over or around
O5: Extreme: large obstacles not passable or requires extensive aid

A1: 0
A2-A4: 1-4

If a specific trail feature is above grade 2, then the general rating can not exceed G1. For example, if a novice trail has a section that has a medium steep pitch (P3), then it should at least be a G2 rating even though it would be a G1 without the P3 pitch. 

By using more specific subcategory ratings, the rider can gauge whether to have an assistant along or select a more suitable trail.