So I was actually referring to Fanning Island. Not sure about Christmas Island. They are both part of Kiribati. From google "Snorkeling and diving: Kiribati is home to some of the most beautiful coral reefs in the world. With clear, warm waters and an abundance of marine life, it's a great destination for snorkeling and diving. Beachcombing: Kiribati's beaches are known for their white sand and crystal-clear waters."