Commemorating the Navy

We watched on TV the impressive displays that took place in Sydney commemorating the centenary of the Australian Navy's entry into Sydney Harbour. (not the centenary of the RAN, even though I saw a couple of news report state this was the case).
The identification of this particular event as being worthy of commemoration may lie in the fact that the timing (and location?) was convenient, rather than it being of any more significance than other events in the history of the RAN!   However, I guess we ought not be churlish about that!
Nevertheless,  let's not forget that there were colonial navies in the era before Federation.  A reminder of this is the anchor and swivel of HMVS Nelson, now located on the foreshore at Williamstown.