Dry Tortugas National Park is a sparkling gem in the Florida Keys. Located about 70 miles west of Key West, and accessible only by boat or seaplane, the park is made up of seven small islands and 100 square miles of crystal clear waters, dreamy coral reefs, and lush gardens.

That’s an excellent question, and the answer depends a bit on what you mean by “clearest” and the conditions on any given day. However, based on consistent geography, water depth, and protection from runoff, a few keys stand out.

Here’s a breakdown, from the most reliably clear to other notable contenders:

The Top Contender: Bahia Honda Key & the Looe Key Area

• Why it’s the clearest: This area benefits from its position farther from the mainland, minimizing silt and freshwater runoff from Florida Bay. The water over the sand and seagrass flats on the oceanside (Atlantic side) of Bahia Honda and around Looe Key (a marine sanctuary a few miles offshore) is often stunningly clear, with visibility frequently exceeding 50 feet on calm days.
• The catch: The famous Bahia Honda State Park beach itself is on the Florida Bay side, which can sometimes have more turbid, warmer water with sea grass. For the clearest water, you need to snorkel or take a boat to the oceanside reefs or Looe Key.

Other Keys with Exceptionally Clear Water:

1. Dry Tortugas (Key West’s Outer Islands):

   • Why: Located 70 miles west of Key West, this is the most remote and pristine part of the Keys. Surrounded by the deep, clean waters of the Gulf of Mexico and home to spectacular coral reefs, the water clarity here is often the absolute best. The trade-off is that it’s only accessible by boat or seaplane.

2. Key Largo (John Pennekamp Coral Reef State Park):