UPDATE 27/8/22 - No need to jump the fence now. The new cache is a micro and can be found near "Signal".
The bottom part of the cache is currently missing - until it gets replaced take a photo of you holding the top half as your log.

Today, this obelisk overlooks the Darwin Harbour Wharf area, from where all men from the Territory left during the First World War. The high cliffs would have been one of the last familiar sights those men would have seen as they sailed off to war. It overlooks the harbour where so many died in the Japanese air attack on 19 February 1942.
Most significant of all, it is sited on the spot from which guns of the 14th Anti-Aircraft Battery went into action, firing, arguably, the first shots ever in defence of Australia on Australian soil.
This memorial was the first official monument of any kind erected in the Northern Territory and funds were subscribed by various organisations and committees throughout the Territory during 1920. The initial chosen site for the memorial was Liberty Square, the area in front of the Administrator’s residence.
A local Darwin cacher Monchichi1 has kindly offered to maintain this cache.
After all this location is all about the monument rather than the cache. 