Abstract: A lighting unit particularly for airports includes a base unit (1) for securing at ground level, and a demountable module (2) including a lamp (9) and a pair of oppositely disposed optical elements (11, 12, 17) for directing the light beam along prescribed light emitting paths. Electrical contacts (6, 16) are respectively mounted on the base (1) and the module (2) for mating together when the module (2) is in place, and are situated in a position which is above ground level when the unit is secured to the ground.