A method of creating an orthomosaic of a corridor area consisting of a strip of land or water along an arbitrary path , which corridor area has a greater length than width, the width being not necessarily constant along the arbitrary path , the arbitrary path being partially describable by a corridor path polyline , the corridor path polyline being not straight, the method comprising: (a) flying an aircraft along a primary flight line, the primary flight line comprising a sequence of straight primary flight line segments , wherein the aircraft is flown level along each primary flight line segment , each primary flight line segment being unaligned with its immediate predecessor (if any) and not parallel to its immediate predecessor , each primary flight line segment approximating part of the corridor path polyline ; (b) capturing, during flight along each primary flight line segment and via an aerial camera system carried by the aircraft, a sequence of primary images, each primary image at least partially overlapping its predecessor in the sequence; (c) flying the aircraft along a secondary flight line, the secondary flight line comprising a sequence of secondary flight line segments , each secondary flight line segment extending parallel to, and laterally offset from, a respective primary flight line segment ; (d) capturing, during flight along each secondary flight line segment and via the aerial camera system carried by the aircraft, a sequence of secondary images, at least some of the secondary images overlapping at least some of the primary images; (e) identifying , in a plurality of the primary images and secondary images, common features corresponding to common ground points; (f) estimating , via bundle adjustment and from the common ground points, an exterior orientation associated with each primary image and a three-dimensional position associated with each ground point; (g) orthorectifying , using at least some of the exterior orientations and at least some of the three-dimensional ground point positions, at least some of the primary images; and (h) merging the orthorectified primary images to create the orthomosaic . (a) flying an aircraft along a primary flight line, the primary flight line comprising a sequence of straight primary flight line segments , wherein the aircraft is flown level along each primary flight line segment , each primary flight line segment being unaligned with its immediate predecessor (if any) and not parallel to its immediate predecessor , each primary flight line segment approximating part of the corridor path polyline ; (b) capturing, during flight along each primary flight line segment and via an aerial camera system carried by the aircraft, a sequence of primary images, each primary image at least partially overlapping its predecessor in the sequence; (c) flying the aircraft along a secondary flight line, the secondary flight line comprising a sequence of secondary flight line segments , each secondary flight line segment extending parallel to, and laterally offset from, a respective primary flight line segment ; (d) capturing, during flight along each secondary flight line segment and via the aerial camera system carried by the aircraft, a sequence of secondary images, at least some of the secondary images overlapping at least some of the primary images; (e) identifying , in a plurality of the primary images and secondary images, common features corresponding to common ground points; (f) estimating , via bundle adjustment and from the common ground points, an exterior orientation associated with each primary image and a three-dimensional position associated with each ground point; (g) orthorectifying , using at least some of the exterior orientations and at least some of the three-dimensional ground point positions, at least some of the primary images; and (h) merging the orthorectified primary images to create the orthomosaic . <EOS>