This unique cave is approximately 200 yards in diameter supplying fresh water at low tides and producing salt water at high tide. Fertile nature trails leads to and from the caves with natural vegetation which produces a variety of herbal remedies referred to as ,bush medicine., The fern gully is also a large fertile ,sink-hole' with indigenous vegetation such as; custard apples, sea grapes, pigeon plums and coco plums. In addition to flowering plants, wide berries and plums that have been historically popular with native residents.