My cousin and I went for an afternoon walk at the Nepean River sometime last winter. It's a nice quiet place where you can go boating, fishing, or on a cruise on one of those classic ferry boats. I suggest if you're looking for a nice, quiet place to relax, have a picnic, take a walk or go for a run, you should come see this place. It's a great city getaway if you aren't a beach patron (it's about 60kms away from Sydney) and it doesn't take to long to get to.
(I'm still pretty much hung up on winter. More substantial blogs soon!)