Heading from the M27: turn off at Junction 3, joining on to the A27 Southampton Road heading to Romsey. Continue on the A27, over the first roundabout. Turn left at the second roundabout and follow the A27 past the Romsey Rapids (and the wall to the Mountbatten Estate on the left).
Take the bypass round to the left at the next large roundabout, Then take a right into Palmerston Street, follow this road around to the left and finally turn right into the Hundred. Complete Security is on the right.