reconnaissance

An inspection or exploration of an area, especially one made to gather military information.

The act or operation of reconnoitering; preliminary examination or survey.

An examination or survey of a region in reference to its general geological character.

An examination of a region as to its general natural features, preparatory to a more particular survey for the purposes of triangulation, or of determining the location of a public work.

An examination of a territory, or of an enemy's position, for the purpose of obtaining information necessary for directing military operations; a preparatory expedition.