The Manly Scenic Walkway goes from the ferry terminal to the Spit Bridge. It takes several hours and is really nice. At times you feel like you are in the bush and no one is around you, then you turn a corner and see the Sydney skyline. Goes along the coast line wit views of the ocean and the bay. It gets a little tricky at the end near some small beaches, so make sure you follow the signs and it is still daylight. We ended up in someone's backyard but were lucky enough to get a ride to the bus stop from a local. Well worth it! Check this for more info - http://www.manly.nsw.gov.au/Manly-Scenic-Walkways.html about 10 years ago
I concur, love the Spit bridge walk.
You can also stroll down to Shelly Beach (and take a dip there, or rather a snorkel), or just follow the coast up north towards Curl Curl lagoon, passing Queenscliff Bay beach and Curl Curl beach (and back again). about 10 years ago