Not many people have discovered this well-kept secret, but I will be kind enough to divulge this mystery.
At Queenscliff Beach, on the far left side of the beach, there is a rock platform leading to a black hole carved out by fishermen around 100 years ago. The fishermen carved out this portal to ward off the monsters of the sea that were stealing their fish. In case you were wondering, my facts are 100% correct. (I asked the fishermen from 100 years ago, they said it was true).
Manly Beach also has a shopping district to help you fuel up for your adventure. Some of the shops can be a little pricey, so stay smart with your budget… or don't. It's your money; you don't have to follow my advice.