This cache is hidden at the start of the creek, that flows into Bullcreek, which in turn feeds the Canning river. It is a small canister similar to a bison tube and therefore only enough room for a log. The best place to park is in Moonlight Cove, and this provides the chance to find the fairy cave, at the same time.
It is unlikely you will come across any muggles so your search should go unhindered.