Cache is a small jam jar, tucked into the base of a tree near a power pole. Location should be fairly obvious once you arrive at the carpark.
When placed it contained 2 swag items, room for small TB's and coins as well.
The Wither Hills Farm Park is a very popular area for walking, running and cycling. From the carpark there is a nice walk up to Mt Vernon, either via Sutherland Stream picnic area, or directly up the ridge. Allow around 1.5 hours to reach the top. Make sure you take some water.
During summer this area is an extreme fire risk so take care, don't smoke, and even watch where you put your water bottle as fires have started from pump bottles being placed down on the grass when taking a rest. There is good cellphone signal throughout most of the park, and water stations are provided at some locations. Have a look at the detailed map board before starting your walk.