Saltdog - I lived in Kirribilli until recently and loved the view of all the yachts crossing back and forth in the harbour and under the bridge. If the
weather was marginal for sailing there would be regattas across the bay, dodging
ferry and big ship traffic - certainly nothing for the faint at heart! Depending upon where in Sysdney you live, you might
head south or a short drive north and you will get to Mona Vale which has a lot of yachts and
marinas as well and might be more enjoyable than the harbour. I might be returning there as well sometime in the next months, just in time to miss autumn in the northern hemisphere and see an Australian spring.
Just to give you an idea - here's a picture taken from my balcony one weekend, the trees at the bottom belong to a well-known Australian residence called "Kirribilli House"