Join the Motorway at Lurgan or Moira and head in the Belfast Direction. Take exit No. 6 (A49) signed to Lisburn (City Centre) and Saintfield and take first exit from roundabout onto Saintfield Road (A49) toward Lisburn City Centre. After 0.3 miles at the Texaco Petrol Station/traffic lights turn right onto Mercer Street and, where the road sweeps round to the right, turn left onto Gregg Street. Keep on this road as it sweeps round to the right becoming Canal Street and continue on to Lagan Valley Island car parks. (NOTE: gate access may be required)
Alternately continue past Texaco Petrol Station on to Sloan Street i.e. don't turn right at traffic lights. Take the right lane and, crossing the Lagan Bridge you will first turn left before swinging round to the right to follow the signs for Belfast (A1) / The Island Civic Centre. The Centre is a few hundred yards along the A1 dual-carriageway on your right. When on the island, drive past the Centre, turn right to cross the bridge and find a parking space.
If all this is too confusing, turn on your satnav and go to Lagan Valley Island, Lisburn, BT27 4RL.