The system (10) has a synthetic environment generating assembly (38) including a database (45B) with topographical information relative to a terrain. A display management assembly (42) controls display of relief lines (304) representative of the terrain on a region of a display (36), without displaying synthetic surface representations of the terrain in intermediate areas. A determination unit determines the position of crest lines of the terrain, and a computing unit (300) computes the position of the relief lines from the position of the crest lines, and based on the position of an aircraft. An independent claim is also included for a viewing method for an aircraft.
