$9 to get up the southern pylon on the bridge, very worthwhile imo, obviously a daytime thing, i think its actually 11 bucks now
night time and sunset on the Kirribilli side – get off at Milsons point and walk east around to all the expensive houses
plenty of city scape shots from here too, take a bottle of wine and a fold up chair and I reckon there are worse ways to spend a sunday evening.
under bridge on the north eastern side
On the southern side just near the rocks, easy access from the city, pleasant walk and good if your at a hotel in the rocks
On the southern side over at Mrs Macquaries Chair, popular, cliche location, its a nice walk from the opera house but watch the closing times of teh Botanical gardens which makes for a longer walk back.
nighttime
or sunrise
and at low tide there is even some rocks for seascaping, also a view towards garden island
And of course there is observatory hill, great location, lots of green grass and a good spot for sunrise at this time of year (with the bridge)
if your keen for a run on the northern side, this is about a 30 min walk from North sydney station, called Blues Point
and you can get both east and west views from here for sunset..