- Ferry to Manley beach, hang out at one of the many beaches and eat at The Boathouse Shelly Beach (best meal I've had in Sydney)
- We saw a play in the opera house, which we really enjoyed. Fun to not just see the outside
- The zoos are great if you are into zoos but personally we liked the wildlife sanctuary types much better. We went to Featherdale and have been to Koala Park on a separate trip. They are smaller but more Australia-centric and more intimate. You feed kangaroos, wallabys, pademelons and koalas. Similarly highly recommend Bonorong if you are going to Tasmania
- Canyoning with this company was a blast https://bmac.com.au/blue-mountains-canyons. You have to get yourself to Katoomba, but either this or hiking in the Blue Mountains is a good alternative to Sydney
- We also did a free walking tour around the rocks, which was really well done. https://imfree.tours/sydney/