Niue is a coral atoll island. As such, much of the island is made of of softer minerals that have been worn away by thousands of years of ocean surf, leaving behind a vast number of incredible landscapes. This one is called Matapa Chasm and features a deep ravine that opens to the ocean. With a few large boulders near the entrance, the inner chasm is pretty protected these days from waves, making it a great swimming hole and it's teaming with marine life.