If you made it all the way to Sydney, try to take the most out of it. Surely you already had the Sydney Opera on your bucket list and you ran to snap a photo of it, but don't just limit yourself onto this.
Go for a walk further, pass the Opera and towards the Royal Botanical Gardens. The path is quite long, you can cycle, jog, rollerskate, etc. I loved how dedicated to sports the aussies were. There are many different plants and trees and each of them is marked with their name in Latin and description. There is wifi in the gardens, so you can just sit on one of the many benches and boost your Instagram and Facebook profile with the many Sydney photos you took.
If you feel like, hop on one of the many ferries at Circular Quay and get a good look of the Opera, The Sydney Harbour Bridge and the city itself. On a sunny day, the views are spectacular. The ferries on Sundays are the cheapest. I suggest taking a government ferry rather than Captain Cook or other ferries. You simply buy an OPAL card from the supermarket and you top it up.
Also, you can go on a day trip to many destinations: Taronga Zoo, Watsons Bay, Manly Beach, Bondi, etc.
Sydney and its surroundings really have a lot to offer and I really encourage you to take advantage of it.
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