R21 highway, Olifantsfontein SITE NUMBER : BB127-10 DESCRIPTION : R21 highway - travelling from PTA towards Kempton Park & ORT Airport. Between Olifantsfontein & Nelmapius off-ramps. SIZE: 4.5m x 18m TRAFFIC : 165 000 /day GPS CO-ORDINATES : -25.923903, 28.262312