The large area collectively known as Chowder Bay in Mosman covers several separate parks that are all part of the Sydney Harbor national park system. This week I did an intense 8km track walk with a dozen mums from Ana's school all around Mosman. Afterwards, I felt convinced I could trek the entirety of Mosman in a day without kids. What a wonderful trek it would be too, Mosman is just beautiful! Here is a great spot I found solo hiking on Sunday off of Chowder Bay rd. It was completely empty when I got there, making it even that more delightful.
An old military outpost off Chowder bay road is open to the public and can be explored (without kids). There are bats in the tunnels, so I opted to stay above ground and scale the cliffs. There are a number of walking tracks to various other locations around Mosman that start here at Chowder bay. It is also home to Mosman's only nudie beach, Obelisk beach. There are two restaurants for both fancy and laid-back live music atmosphere goers, a large pier, and of course tight parking. I definitely want to take my sister-in-laws here if they come in August, just not to the nudie beach.
Taken from sign post: "In 1890 a base was built at Chowder Bay for the Submarine Mining Corp. Mines were attached to cables that went underwater from here to the other side of the harbor. They were designed to be detonated if an enemy ship entered the harbor. In 1891 a terrible accident happened with the Mine Corp demonstrated mine laying before a crowd of thousands. Four men were killed and 10 more injured. With changes in technology, these mines became ineffective and were eventually disbanded in 1922."