Always was and always will be Darkinjung country, Forresters Beach is apparently named after a bloke called Forrester who purchased land in the area in 1861.
The descent to the beach used to be a real trial - a crumbly dirt path or tortuous stairs were the choices. Now the blue stairway to the sand makes it much more comfortable. There is even a nice bench halfway down to take a break and admire the view.
The cache container is attached to portal infrastructure. It is magnetic, so that is a clue in itself. No need to climb under stairs or jump fences or wire boundaries - it is a matter of bending over and inserting your hand. Be warned - it is a high traffic area, so discretion and stealth will definitely be required in daylight hours. It was originally placed in the dark, so finding it in the dark should be possible too.
When putting the log back in the container, roll it tightly and put it back in the lid, not the body. You'll see why if you do it the other way around.