The posted coordinates of this cache DO NOT indicate it's true location. To determine where this cache is, track the course of the Tank Stream from Sydney Harbour back upstream to its origin.
The Tank Stream was the original fresh water supply for the new colony of Sydney and is the reason that Sydney is where it is today. The stream was fed by springs that were situated in swampy ground in the area bounded by Elizabeth, Pitt, Market and Park Streets and are marked by the listed coordinates for this cache. The name "Tank Stream" comes from the tanks that were excavated in sandstone (near the present day Australia Square precinct) to collect and conserve the valuable water during times of drought.
Today, the springs are covered with the concrete of the modern Sydney CBD and the Tank Stream is little more than a storm water drain. However you can trace its course by visiting a series of art installations commemorating the Tank Stream created by Lynne Roberts-Goodwin in 1999.
The installations are one or two steel elements with glass set in the pavement and inscribed with a quote from 1788 by Captain Watkin Tench, a British Marine Officer in the First Fleet:
"Into the head of the cove, on which our establishment is fixed, runs a small stream of fresh water, which serves to divide the adjacent country to a little distance, in the direction of north and south."
The location of each installation is marked by the child waypoints listed for this cache (there is also one inside the City Recital Hall but it doesn't form part of this cache). The walk will take about an hour to complete. By collecting information at each site, you will be able to calculate the true coordinates of the cache. Ignoring decimal points, calculate the coordinates using the waypoint information as follows:
- Southing = 3352295 + k + ( i / j ) - 2
- Easting = 15112542 + ( 2 * x ) + y + ( 8 * z )
The cache is lunch box sized and contains a log, pencil and has room for a few swaps and a travel bug or two. Please close the container and replace carefully and watch out for the ever-present muggles in this area.
Read more about the Tank Stream and this walk at Creative Spirits.