I've wanted to see the Tank Stream, Sydney's first water source, for a long time. While it provided clean water to the original white settlers, it quickly became polluted and these days is little more than a sewer. It was replaced by Busby's Bore in 1830 following Sydney's first major engineering project cost and time blowout, a tradition followed today by all major engineering projects in the state.
Anyway, in February this year I found a form on the Historic Houses Trust site that claimed I would be notified when the next ballot for tours of the Tank Stream were being announced. Except they didn't tell me that there's there'll be tours next month as part of the Sydney Open 08 thing, which sees a bunch of properties open for tours.
Fortunately I spotted it and put today into my calendar. I now have tickets to do the tour on 2nd November. If you want to see the Tank Stream, get in now. We're doing the 15:45 tour.