Abstract: An improved radar retro-reflector providing overlapping coverage at low angles of elevation comprises a plurality of three-corner retro-reflectors made of electromagnetically reflective material lying in three planes which intersect each other at right angles. The individual retro-reflectors are supported between a horizontal base and a platform mounted above the base, and are interconnected to each other and to the base and to the platform in a geodesic configuration. Additional three-corner reflectors may be mounted atop the platform in back-to-back configuration. The radar retro-reflector may be foldable into a compact generally flattened storage position by making the device out of a plurality of hingedly connected triangular panels controlled by a hydraulic or other actuating system.