Difficulty evaluation
Technique
Grade Path, terrain Requirements
T1 Walking Good track / path Flat or slightly inclined terrain, no falling risk Comfortable walking shoes
T2 Mountain hiking   Path with continuous track bed Sometimes steep terrain, slight risk of falling (rocks) / feet slipping. Competent, agile.
Quality Trekking shoes
T3 Challenging mountainhiking Paths not always visible, some exposed places secured with ropes or chains, hands needed for balance / grip ropes. Partially exposed sections with risk of slipping/ gravel / unexpected changes in path and terrain. Previous experience and competent agility needed.  Basic to medium alpine experience needed. Appropriate shoes..
T4 Alpine Hiking Paths not always available – hands needed to grip ropes/ at times. . Terrain quite exposed, tricky grassy slopes, abrupt changes to paths, snow-free glacier paths and paths/treks through fir forests Confidence in exposed terrain, good, robust trekkingshoes Previous alpine experience, Due to weather changes can be difficult to retreat
T5 ChallengingAlpine Hiking Varies between no tracks to grassy/easy climbs Exposed, challenging terrain, steep paths/ changing terrain/ glacier and snow fields routes with risks of slipping/falling. Mountain shoes Good alpine experience needed with some previous experience of pick and rope
T6 DifficultAlpine Hiking Mostly pathless, climbing sections up to second difficulty grade (IUAA scale) Often very exposed, very steep terrain, glacier sections with increased risk of slipping Advanced alpine experience needed with previous experience/ confidence using alpine technical auxiliary tools.
Source: Schweizer Alpen Club