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.
Happy Valley, Hong Kong
On 19 December 1941, the Japanese Imperial Army entered the hill east of the valley and fought their way to Blue Pool Road. On (now Blue Pool Road) a number of large massacres occurred, most notably the Blue Pool Road Massacre, where civilians were bayoneted. Civilians and Soldiers captured were kept in the appalling conditions of 'the black hole of Hong Kong' (a house on Blue Pool Road). The Japanese later advanced up to Wong Nai Chung Gap, where the battle of Wong Nai Chung gap occurred, resulting in Japanese control of the gap. Although the low-areas of Happy Valley were captured, areas surrounding Leighton hill and Morrison Hill were still contested until later in the Battle of Hong Kong.