Ah yes, City Beach and the Park. It's been a popular place for decades. I'm guessing the first photo was taken in the late 1940's. Note where the steps go from the park, a ramp crosses the beach and goes out to the docks. Fully dressed people, including a sailor, are on the dock.
The lower photo was probably taken in the late 1950's. You can see more docks and Playland Pier in the background. The porthole windows were the doors on changing rooms. Those were removed in later years, I don't remember them. Also visible are the carousel, rockoplane, ferris wheel and swings. The swings were a favorite because you literally swung out over the water on the ride. The buildings behind housed the bumper cars, the arcade and snack bar.