Mitiaro, the fourth island in the Cook Islands group, is of volcanic origin. Standing in water 14,750 feet deep (4500 m) it is four miles (6.4 km) across at its widest point.

Mitiaro, the fourth island in the Cook Islands group, is of volcanic origin. Standing in water 14,750 feet deep (4500 m) it is four miles (6.4 km) across at its widest point.