well we went to the Sydney aquarium. Cost me $80 for 2 adults and 2 kids. I enjoyed it as it was not too busy and the Sydney waterfront was very mellow for a change(and this on a Saturday Afternoon). It must be because Winter is almost here. Took us about an hour and a half to go through everything and it covers sharks, doguns, coral reef and the various river regions in Australia.
I liked it, it was quite a bit bigger than the Cape Town one and there are some nice underwater walkways.
Its in Darling Harbour and can be reached by all the usual transports - car, bus, train, ferry etc. We took the car and parked in a parking garage in Sydney for a $10 flat rate. You just walk to the waterfront which is 2 blocks.
Watch out for the gift shop you go through when you leave, My wife and two eleven year old girls were oohing and aahing and there was a another til-kaching on the way out :)
But good fun, with some restaurants on the waterfront or just double scoop ice-creams all round etc.
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