When we climbed the Sydney Harbour bridge with my parents last month we were given free tickets to climb up one of the huge stone pylons supporting the bridge to a great lookout spot. Of course on our one day off it was overcast! Typical!
In fact after climbing up lots of steps, reading all about the history of the bridge we finally got to the top and it was raining! Haha. But it didn't dampen our spirits (see what I did there). The view was still amazing of both the bridge and the city.
The climb costs just $13 so if you're ever in Sydney and can't afford to do the main bridge climb this is definitely a great alternative to get some fantastic photos of the city. But of course nothing could out do the experience of the bridge climb itself :)