On the Rail Trail between Clyde and Alexandra is the Racecourse. Cache cannot be accessed through the Racecourse but from the start of the Rail Trail at Clyde or a little closer by parking on Coates Road and walking/cycling back towards Clyde. Coates Road is between Airport Road and Dunstan Road but still shows up on the geocaching Map as Airport Road which it was formerly known as.
From GZ there are lovely views all around including Leaning Rock to the North - known locally as The Old Woman - it is the largest of a spectacular group of huge tors (rock shafts) on the summit of the Dunstan Range. The Old Man Range is to the South and has nothing higher between it and the South Pole. It is quite likely on a nice day you will see a small plane/planes flying around being that the Airport is to the North East. Cache is a 450ml snaplock container placed at ground level.