Blue Hole Freshwater Lake – Big Pine Key, Florida - Atlas Obscura
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Big Pine Key, Florida

Blue Hole Freshwater Lake

The only freshwater lake in the Florida Keys. 

The Florida Keys are known for their natural beauty and oceanic wildlife, from the coral reefs sitting just offshore to the diverse marine population that attracts coastal kayakers and sport-fishermen from around the world. The only thing visitors won’t find, in fact, is freshwater — except for one oasis.

Sitting in the middle Big Pine Key — of one of the largest islands in the chain — an abandoned rock quarry forms a freshwater lake now known as the Blue Hole. Henry Flagler’s company cut rock out of this quarry to build his famous overseas railroad, now long gone along with the quarry itself — reclaimed by nature and, in parts, modernity.

The Blue Hole forms the epicenter of the Florida Keys National Wildlife Refuge, and more specifically the National Key Deer Refuge — a large expanse of reserved forest meant to house and preserve the unique Key Deer (a miniature and endangered species of deer), which only live on Big Pine Key.

Since it’s such a large source of fresh water, the Blue Hole attracts multitudes of wildlife unique to the Keys beyond just the Key Deer, including large invasive iguanas, tropical birds, various snakes, and reptiles, and of course the Florida Alligator — missing from most parts of the Keys but happy to live and bask in this oasis.

Know Before You Go

Drive down the Overseas Highway (US 1) to Big Pine Key and head down 21st Street (Key Deer Blvd) until you see signs for the refuge/Blue Hole.