The most important info - We won't have a car

What we want: excursions from Sydney that can be done without an overnight stay.

We've been to Sydney before, and love it. This time, we'd like to use it as a base to explore some of the surrounding areas. Jervis Bay was recommended, but that's 2.5 hrs away. Any suggestions would be greatly appreciated!

The most obvious would be the Blue Mtns. You can take a CityRail train (http://www.cityrail.info/timetable/t...=wd&dir=dn) to Katoomba (http://www.bluemts.com.au/tourist/towns/Katoomba.asp), where there are a number of activities in short walking distance from each other. You could go on a nice hike past the Three Sisters, take a SkyRail cable car ride, or take the inclined railway.

Jervis Bay is wonderful, but it does need a car. I think there may be some tours - I'm sure I saw one advertised.

Of course, there's the Blue Mountains, reasonably easily done by public transport.

The Spit to Manly walk, and Bondi to Bronte walk are both fun, nice views, and decent cafes at the end, with public transport both ways.

Another option is the train to Brooklyn, and a day wandering the river, with the River Postman. I can try and find out a bit about this, if you're interested.

Get the sea plane from Rose Bay to Pittwater.

Climb Barrenjoey
Have a surf
have lunch

Get the ferry from palm beach to Ettalong across Broken Bay

Bus/train back to sydney.

Thanks! These are great ideas that I didn't even know we could try. We've done the Bondi-Bronte walk, but may again, and are scheduled to try spit-Manly. Sea plane, ferry...? I better start researching.