Mona Vale rockpool, Sydney, Australia

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A shore thing. Mona Vale rockpool, Sydney, Australia

Ever wanted to swim in the ocean without accidentally tasting half of it? Enter Mona Vale rockpool in Sydney, Australia—a watery paradox where the ocean is wild beyond the walls and well-behaved within its calm, contained edges. Perched between two beaches—The Basin beach and Mona Vale Beach—this rock pool feels more like a natural wonder than a man-made one. Built in the 1930s during the Depression, it was carved out of a natural rock shelf as part of an unemployment relief scheme. Upgraded over time, the pool is more than 30 metres long and flanked by a smaller children's pool. The pools were also used by large numbers of World War II troops who camped nearby. They are free, open year-round and cleaned regularly by both council crews and the ocean itself. So next time you are in Sydney, make a splash where the waves meet the wall. It's a shore thing.