Easy
Gradients - Shallow
Surface - Compacted surface 2-3 m wide and forest roads
Suitable for - Occasional cyclists and families

Moderate
Gradients - Moderate with some steep sections that may have to be walked
Surface - Compacted surface 2-3 m wide with up to 10% on rough tracks under 2m wide
Suitable for - Novice cyclists and families

Difficult
Gradients - Steep
Surface - Width below 1m wide with a range of surfaces including rough narrow tracks
Suitable for - Good cyclists with mountain bikes

Severe
Gradients - Steep with drop offs
Surface - Mostly on rough narrow tracks
Suitable for - Expert mountain bikers