Easy

You like to walk to get exercise and enjoy strolls in the countryside.
You don’t need to be an athlete to enjoy these trips.
Walks from 2 - 4 hours on easy terrain, with minimal climbing.

Moderate

You practise regular and sustained exercise (whether walking, cycling, aerobics, etc.) You are keen to set off on all-day walks.
Walks from 4 - 6 hours on various types of terrain, up to 600m/2000ft of climbing per day.

Challenging

You are in good shape, and you practise regular and sustained exercise, lasting up to several hours at a time.  You have hiking experience and can negotiate rocky, technical terrain.
Walks from 4 - 7 hours, and up to 1000m/3300ft of elevation gain per day.