Santa Rosa, NM: This is the most famous of the many bodies of water in this vicinity suitable for skin/scuba diving. It is said to be some eighty feet deep.

Blue Hole National Park is a national park located just off the Hummingbird Highway in Cayo District of Belize, near Belmopan, the capital city. It is over 500 acres (2 km²) in area, and contains two cave systems (St. Hermans and Crystal), various natural trails, and the cool jungle pool from which the park gets its name.

Blue Hole is a diving location on east Sinai, a few kilometres north of Dahab on the coast of the Red Sea.

The term blue hole is usually used to refer to a submarine cave or sinkhole; in some scientific circles however, these are more specifically called "black holes", or "vertical caves".http://www.blueholes.org/pubpdf/symposia.pdf