Some people may be aware of the TV show 'Guerrilla Gardeners',
which didn't quite complete its season on air. In case you don't,
or have forgotten, Ten still has a website up and
running.
There are two geocaches in Sydney located at some examples of
their work - Wool-Loo-Moo-Loo
(GC1Q8B4) and Guerrilla
Gardeners (GC12Q2VW).
Recently on the way to work I passed by this one, which I didn't
recall seeing on air. Turns out this was one of three that were
recorded, but never made it to air. So you get to see it.

It's an interesting location on the corner of Wilde and Phillip
Streets in Parramatta. The small corner block has been converted
into a small oasis complete with bocce area. While the benches get
used, the boci area doesn't appear to.
The cache is a small 0.5 litre sistema, suitable to hold small
swaps. The container contains a magnet that lines up with a large
washer attached to the side of the bench to help hold the cache in
place.
