OZ
Russel Road , just off Hawthorne Road , turn left at the lights , so soon you pass ( Hydro Road ) located on your left , you will see a power plant , just across from the power plant and before you reach Calvary Christian Reformed Church Reformed ( USE google maps satellite option it shows perfectly the whole path ) , there is on your right hand a GRAVEL path...Is is wide enough for car drive - in comfortable , the path is so long that it almost connect all way back to Hawthorne Road ,but is a dead end , with trees /nature both sides , completely private and discreet , so soon you drive- in there is a small play area on your right side if you choose dont go deep into the path , plus it is perfect to turn the car around to face the road on your way out if you decide to go deep into the path with your car ,on the path you can easily fit 10+ cars in there ( one behind the other one ) and keep a decent space between cars enough to place thick blankets on the ground , now IMAGINE if a large group of people decide to keep the cars around the parking /play area and bring their things just a couple meters farther into the path ,, you can fit 20 -30 + people in there 
. Google Maps is your best friend , just google the church name