Wattamolla, also known as Wattamolla Beach, is a cove, lagoon, and beach on the New South Wales coast south of Sydney, within the Royal National Park. It stands at approximately 12.5m tall. Many tourists are drawn to the giant cave situated 500mm below the waters surface and can only be accessed by diving under and following the shaft of a tunnel …Wattamolla, also known as Wattamolla Beach, is a cove, lagoon, and beach on the New South Wales coast south of Sydney, within the Royal National Park. It stands at approximately 12.5m tall. Many tourists are drawn to the giant cave situated 500mm below the waters surface and can only be accessed by diving under and following the shaft of a tunnel submerged with water into the cliff face for roughly 2m until a massive opening has you standing in a giant hidden cave.