Hi SolidA,
The family and I lived in Sydney for nearly two years about 7 years ago. I have been to a lot of cities in the world and Sydney is one of the nicest around. Lots of things to do, people are very friendly, crime is low, and the area is just gorgeous. The Sydney harbour is the most beautiful harbor in the world!
We made two trips to the Barrier Reef during our stay there. Both trips were in the winter there, june/july, about the same time you are going. Unfortunately for us, both times we were there it was rather windy and cloudy. It may be like that a lot in the tropics that time of year, I’m not sure. We stayed in Port Douglas (the hotel across the street from where the Clintons stayed at the Sheraton). We went snorkeling twice out on the reef. We ended up going to the outer reef, which is a very long boat ride out there. Due to the wind, the swell was very strong, so most of the dozen tourists on the boat had an hour-long hurling contest!! Whew! Fortunately for me I grew up salt-water fishing off the California coast so I was used to being bounced around on a boat. The swell kicked up the sand enough so that the visibility wasn’t what I really had hoped for. It was still very awesome, but just not quite like the “Jacque Cousteua” experience I had been envisioning. Later, we found out that for good snorkeling/diving you don’t necessarily have to go all the way out to the outer reef, so you can take much shorter trips to the inner reef. Additionally we considered going to a hotel/resort on the many islands out on the reef (Lizard Island, Heron Island, Hamilton Island, Green Island, etc.) so we wouldn’t have to take long boat rides to have fun in the water. But with VERY young kids with us we felt it wasn’t worth the additional cost.
The winter-time up there is not the time for the dreaded and deadly box jellyfish. The beaches all have net enclosures to keep these nasty jellyfish out. However, after having been stung by blue-bottle jellyfish (Blueies) on the Sydney beaches, I really didn’t feel like taking any chances! All it would take is a very small chunk of a dead box jellyfish to come through the nets are you could have a very bad sting! But out on the reefs, there are no box jellyfish so, no worries! The box jellyfish come from the many estuaries along the coastline. On both our snorkeling trips, no one was wearing wet suits. Oh, and they had many posted signs warning about the salt-water crocidiles (Salties) along the beaches. We never saw any.
There are many more adventurous trips you can take out of the Port Douglas area, but since we had young kids with us we had to tame it down a few notches.
If you plan on spending anytime around the Sydney area, you will have plenty to do to keep you busy! A boat tour around the harbour is a must. Just walking around the Royal Botanical gardens is very beautiful, and as another poster pointed out, you can see all the fruit bats hanging from the fig trees! The Sydney Aquirium is awesome if you like that sort of thing. Seeing as you will be there in the winter, consider taking in an Australian Rules Football (Footy) at the Syndey Football stadium. It makes the American football players seem like out-of-shape wimps! And these guys are not wearing any pads or helmets. If you have time, you could visit the Hunter Vally wine region about an hour north of Sydney. South out of Sydney the countryside is stunning (if you have seen the movie “Babe” that was filmed there, the Southern Highlands I think it is called). We took a trip about an hour or two south of Sydney to a beach where the kangaroos “congregate”. It is pretty amazing to see all these Roos hanging out on the beach. Mind you, unlike US coastline, there is nothing else around.
I could go on and on. If you have anything more specific you would like to know, don’t hesitate to ask.
Oh by the way, if you go to Sydney make sure you have an umbrella handy. They get around 45in/year of the wet stuff, and it is pretty evenly distributed throughout the year. And it can get on the very cool side sometimes there in the winter (similar to San Francisco) .
Good luck and have a great trip!