The route follows a tarsealed accessway nearly all the way to the cache. Pleasant walking, suitable for kids, with more than a few scenic highlights and pleasant surprises along the way. It is possible to get a pushchair within 10 metres of the cache, though it's a long push back up the hill.
One intrepid cacher has even roller bladed down the accessway; his GPSr recording speeds of 22 km/hr as he sped terrified to the bottom (or almost certain oblivion!).
In the 19th Century the water supply from Auckland was initially drawn from (what is now) the Auckland Domain duck pond. Later in the 1870's a steam pumping engine was installed at Western Springs to tap into this water source. The beam pumping engine and Victorian brick building are now part of the MOTAT museum, at Western Springs.
By the early 1900's temporary timber dams were installed in several locations around the current Waitakere Dam to alleviate water shortages. Construction of the main concrete dam was completed in 1910. Later investigations showed that the concrete dam could be increased in height by 4 metres to provide more water storage. The dam was raised by adding more concrete to the existing dam in 1926. To allow for raising the water level, a nearby low saddle on the edge of the water catchment was dammed with earth fill creating the Saddle Dam.
After more than 80 years of service the dam was ready for a clean-up. In 1993, the dam was given a modern retrofit and overhaul, ready for the next 100 years of service. The work included earthquake strengthening and better securing the dam; our knowledge of concrete dams has improved markedly in the last 80 years.
The cache is hidden just off the main track. The coordinates will take you to near a large green survey marker post. Look through the bush to another identical survey marker some 10 - 15 metres away. The cache is roughly between the two markers.