The compass is an important tool for the excursionists’ guidance; it is used to measure directions on the field. The compass can be used alone or together with topographical charts but in case no chart is available compass is useful for:

• Measuring the courses (angles with respect to the magnetic north) where we may find references we may observe in the field.

• Indicating the trend of a given course

• Going towards a constant direction

• Measuring distances in the field (by means of a trigonometric estimation)

There are several kinds of compasses but the ones mostly used for trekking; land explorations, expeditions or path followings are   the cartographical and the lensatic ones