This is a simple cache in a little out of the way part of the Cardinia Reservoir Park.
The reservoir is a holding dam for Melbourne Water's supply to the South Eastern suburbs and the Mornington Peninsula. Melbourne is very lucky in that we are one of the few cities in the world that receives our drinking water from closed forest catchments, meaning our water isn't contaminated by chemical run-off from farm land. The water in this dam has been pumped from the Thompson, Upper Yarra dams and other smaller catchments, as well, water from the desalination plant at Wonthaggi. You can read about our water network from information boards at the carparks on the dam wall.
The park has toilets, lots of picnic tables, BYO BBQ at the moment, although there is a new gas BBQ at Crystal Brook Picnic Area, loads of walking tracks, kangaroos, a playground and plenty of open space. It is very popular on nice weekend in the warmer months, so get there early to grab a good spot. The sign at the gate indicates that it is open from dawn to dusk, but the website says varying hours depending on the time of year. Here is a link to Parks Vic information. http://parkweb.vic.gov.au/explore/parks/cardinia-reservoir-parks
The cache is located just of a 4X4 track through a lovely stand of mixed eucalypt species with a heathy, grassy understorey. You are looking for a one litre Sistema camo painted container. Please re-hide it properly for the enjoyment of future cachers.