Blue Hole (Big Pine Key)
The Blue Hole is an attraction on the island of Big Pine Key in the Florida Keys. It is an abandoned rock quarry that was used for nearby road fills and Henry Flagler's Overseas Railroad. The water it contains is mostly fresh and is used by various wildlife in the area, such as birds, snakes, alligators, key deer and green iguanas. It is part of the National Key Deer Refuge.
Blue Gum Forest, Blue Mountains
The Blue Gum Forest is a protected nature reserve located in the Grose Valley of the Blue Mountains, in Blue Mountains National Park, in New South Wales west of Sydney, southeastern Australia. It is one of the best-known bushwalking sites in Australia. As part of the Greater Blue Mountains, the forest is within the UNESCO World Heritage Site. The forest survived through the efforts of early Australian conservationists.