This is a great walk for people of all abilities. Take the bus from outside the Manly ferry up to North Head. Get off by the information centre then walk into North Fort and across the Army Barracks - there are lots of interesting buildings to see. There are maps along the way so you can easily find your way even if you dont have a map on your phone.
Once across the Barracks you need to head right to meet up with the parade track - from there walk to the left until you see a small path on your right. You can follow this bush track down into Shelley beach, you even get to go through the old brick fence!
Beautiful views coming into the back of Shelley beach across Manly, Freshwater, Curl Curl etc!
Enjoy a cold drink or snack at the Boathouse in Shelley beach before wandering back to Manly.