Blue Hole (Red Sea)
The Blue Hole is a diving location on the southeast Sinai, a few kilometres north of Dahab, Egypt on the coast of the Red Sea.
Blue Lake (New South Wales)
The Blue Lake is one of only four cirque lakes found in mainland Australia. The other three, Cootapatamba, Albina, and Club, are shallower and are held entirely by terminal moraines. Blue Lake's valley contains the best-developed glacial features in the Kosciuszko National Park alpine area of New South Wales. It was recognised as a wetland of international importance on 17 March 1996 when a area, comprising the lake and its surrounds, including nearby Hedley Tarn, was designated Ramsar Site 800 under the Ramsar Convention on wetlands. The lake lies within the Australian Alps National Parks and Reserves.