listed in the phone book!!!!!!!, its shown on all the A - Z's down here quite clearly as Air Traffic Control Centre.
Bottom of M3 stay in outside lane to head eastbound M27 (yes I know that sounds odd) Leave at junc 8 and pass back under motorway and back up the hill on dual carrigeway. At roundabout take a left and drop down hill, watch your speed as it passes from a 40 into a 30. As you pass over the river take a left at the traffic lights and stick to 30. Another favorite spot for the old bill to catch us in our band 5 cars. Follow this for about a mile back over motorway and you will see an entrance on the left hand side.
Pull into car park before barrier as I guess you will need a pass from the hitlers on the gate.
Easy as that.