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Snorkeling and Scuba Diving Key Largo and the Upper Keys



You deflate your BCD and you and your dive buddy start your descent for your first dive of the day. The water is warm and crystal clear, you can see the coral reef just 30 feet (ca. 9 m) below you. When you reach the reef, you are in awe at the number and different types of reef fish around you and this incredible reef. Above you, you can see snorkelers watching as well. Are you diving on a Caribbean island? Or maybe an exotic Pacific Island destination? No, You are scuba diving Key Largo and the Upper Keys, the islands you can drive to.


Are you looking for a destination with perfect scuba diving or snorkeling conditions? A place with year-round diving, great visibility, warm waters, abundant marine life, and an outstanding selection of reefs and shipwrecks? It may be closer and easier to get to than you think. Scuba diving Key Largo and the Upper Keys may be exactly what you are looking for.

You can be Scuba diving Key Largo and the Upper Keys in just an hour after arriving in Miami. Diving is found in Florida State parks, federal marine parks, and federal marine sanctuaries. There is diving for the beginning diver to advance technical divers. You will also find outstanding sites for snorkeling.


What are the Florida Keys?


The Florida Keys is an archipelago that stretches over 120 miles (ca. 193 km) in the lagoon of the Florida Reef. The Florida Reef, at around 350 miles (ca. 563 km) long, is the third-largest barrier reef in the world and the only one in the Continental United States. The reef is home to 500 species of fish, more than 40 species of stony corals, and 1,400 species of marine plants and animals. Over the centuries, more than a thousand ships have sunk after hitting a portion of the reef system.


Tourism is the main industry for the keys, with over 2.5 million tourists each year having over 5 million tourist visits. Scuba diving and snorkeling is the leading activity for these tourists. The Florida Keys are divided into five regions: Key Largo, Islamorada, Marathon, Big Pine and Lower Keys, and Key West. However, you will often see Key Largo and Islamorada grouped together as Key Largo and the Upper Keys. Marathon is grouped with the Upper Key in some associations or listed separately as the Middle Keys. Key West and the Lower Keys are often grouped together. This article will focus on Key Largo and the Upper Keys.



Why Should You Be Scuba Diving Key Largo and the Upper Keys?


While there is great diving in all the Florida Keys, Key Largo has a reputation as the best diving in the world and attracts the most divers in the US. While there are a number of deep dives and more difficult dives, it is important to note that Scuba Diving Key Largo and the Upper Keys are for everyone. This area is also the leading destination for snorkelers. Many of the dive sites are in shallow protected waters and the visibility is great. This means longer dives and great photography conditions for divers, and great experiences for snorkelers.


The waters around the Key's are all under the control of NOAA's Florida Keys National Marine Sanctuary. There are also some State-controlled parks within that system, such as the John Pennekamp Coral Reef State Park. This state park was the first underwater park in the United States. The park is 25 miles (ca. 40 km) long and extends to the limit of Florida state waters, 3 nautical miles. The water portion of the park includes 70 square nautical miles. There are 75 moored diving sites here.


Just south of Key Largo are the group of Keys that make up Islamorada. There are four Keys accessible from the highway: Plantation Key, Windley Key, Upper Matecumbe Key, Lower Matecumbe Key, and two offshore islands: Indian Key and Lignumvitae Key. Islamorada has additional dive sites off its shores. Some of Islamorada's dive centers also travel to southern sites of the John Pennekamp Coral Reef State Park.


What Makes The Diving So Special

Most reefs form near the coastline and work their way to deeper water. A barrier reef, however, starts at the edge of deep water and grows towards the shore leaving a lagoon of shallow water between the reef and the coast. The coast side of the Florida Reef is four to six miles away from the shore. Close enough to travel too and far enough away to remain natural. Many of these reefs are Spur and Groove formations. This type of reef formation is found in waters as deep as 100 feet (ca. 30 m). While some reefs are exposed at low tide, the average depth of the reefs are in the 20 feet (ca. 6 m) to 60 feet (ca. 18 m) range. Couple the protected waters with shallow depths and great visibility gives you great diving and snorkeling sites.



Key Largo has over a dozen areas to dive each with multiple dive sites. I am sure you could find a diver for each of these sites who will declare it is the best. Still, a few areas and dive sites do stand out. Here is a short description of some very popular sites.

  • Christ of the Abyss & Grecian Rocks: This area, also called Dry Rocks, has seven sites. Three of which focus on the Christ of the Abyss. Even non-divers will likely recognize photographs of this dive site. The Christ of the Abyss is a bronze statue sitting on a concrete base in 25 feet (ca. 8 m) of water. The statue is one of three casts from a mold by the Italian sculptor, Guido Galletti. As outstanding the statue is itself, the reef is well worth the visit as well. The average depth of the reef around the statue is 15 feet (ca 4.5 m) to 45 feet (ca. 14 m) with healthy coral and abundant reef fish. The shallow depth and colorful marine life, make this one of the most photographed dive sites in the world. Three of the sites are reserved for snorkeling being only 10 feet (ca. 3 m) deep.

  • Spiegel Grove (Wreck): This is one of the best wreck dives in the world. The USS Spiegel Grove (LSD-36) is a Landing Ship Dock built in 1954 and was decommissioned in 1989. It is 510 feet (ca. 155 m) long and 84 feet (ca. 26 m) wide. Later, the ship was transferred to the State of Florida to be used as an artificial reef. The cost to prepare the ship to be sunk was over a million dollars, and by May 2002 it was ready. However, the sinking did not go as planned. The ship ended upside down with its bow out of the water. The state spent another $250,000 to roll the ship on its side and flat. Imagine the diver's surprise three years later when in July 2005, Hurricane Dennis moved the ship and set it upright. This wreck has 8 mooring sites on it with dives between 65 feet (ca. 20 m) and 130 feet (ca. 40 m). Due to the size of the wreck and the depth, it takes multiple dives to see the entire outside of the wreck. When the ship was prepared to be sunk, additional access points were made for wreck divers to enter the ship. Certified wreck divers have multiple decks they can explore.

  • Molasses Reef: This reef with its 10 dive sites is the most popular destination in the Florida Keys. While everyone seems to want to dive the Christ of the Abyss at least once, Molasses Reef has divers coming back often. The average dive site is around 25 feet (ca. 8 m) to 40 feet (ca. 12 m) deep. However, there are some areas as shallow as 10 feet (ca. 3 m) and others as deep as 90 feet (ca. 27 m). There are two deeper sites along the eastern edge of the reef. Dropping to 90 feet (ca. 27 m) and having an open channel, these areas are subject to mild currents. The currents are strong enough to make great drift dives. Eagle Rays are found on many of the shallow dive sites along with groupers and reef fish. Green Moray Eels, Southern Stingrays, Turtles, Nurse Sharks, and Reef Sharks are also commonly found among the large coral heads.

  • USCG Bibb and USCG Duane are two sister ships sunk in 120 feet (ca. 37 m) of water. These were 327 foot (ca. 100 m) long Coast Guard Cutters. The USCG Duane's crow's nest is in 60 feet (ca. 18 m) of water and her main deck is at 100 feet (ca. 30 m) making this a good dive site for Advanced Open Water Divers. The USCG Bibb, however, is on her side and only reaches up to 100 feet (ca. 30 m).

  • Conch Reef and Wall: There are four dive sites here. Three are shallow and mostly for snorkelers and Open Water Divers. The fourth is Conch Wall and one of my favorite dive sites. The top of the reef is at about 55 feet (ca. 17 m). The wall drops to 100 feet (ca. 30 m) with a mild current running along with it. Great for a drift dive. Groupers, Turtles, Manta Rays, and Caribbean Reef Sharks can be found among the reef fish, gorgonian coral, and large barrel sponges.


  • Alligator Reef is located near Islamorada's Upper Matecumbe Key. Alligator Reef Sanctuary Preservation Area (SPA) is one of the most popular snorkeling sites in the Keys. The area around the reef's light is less than 20 feet (ca. 6 m), has crystal clear waters, and has no currents. Divers can enjoy dives down to 95 feet (ca. 29 m) and will see many pelagics. Do not be concerned about the name, there are no alligators here. The name comes from the USS Alligator which struck the reef in 1822 and was destroyed. And now the rest of the story. I said there are no Alligators there, and it seems that includes the USS Alligator. More than 160 years after the loss of the ship Naval investigators determined that what everyone believed to be the ship was not. The true name of the wreck and where the real ship is, is not known.

Conservation and Preserving Our Reefs

Everyone should care about our environment. As Scuba divers and snorkelers we often see firsthand the negative impact man has on the oceans. When you start looking for a dive center to use for your Florida Keys diving trip, please use one that pledges to NOAA's Bluestar program.


If you have an interest in restoring coral reefs, consider looking at I.CARE https://www.icareaboutcoral.org/ This organization has a program with a few local dive centers. You spend the morning with them learning about coral reefs and in the afternoon doing two dives. One dive will be to plant new corals and the second checking on transplants.


You Can Not Get Lost on the Overseas Highway.


The Florida Keys, the “Islands You Can Drive Too”, has a unique address system that can be confusing if you are not familiar with it. US Highway1 starts in Key West and continues north and ends at the US/Canadian border in Maine.


The first 120 miles (ca. 193 km) are in the Florida Keys and across 42 different bridges. When the highway was originally built, bridges of an existing railroad were used. The railway was called the Overseas Railroad, and the road became known as the Overseas Highway. US 1 is the only major north-south road in the Keys and on some Keys the only road.


US highways have a mile marker every mile with a smaller marker every tenth of a mile. In the Keys you will often see a location stated as MM followed by a number, it is also used as part of an address. The address will be a 4, 5, or 6 digit number. The last 3 numbers will tell you how close it is to the next mile marker. MM 0 is at Key West.



Let's use the History Of Diving Museum as an example. The Museum is located at Mile Marker 83 on US-1 in Islamorada, on the Bay Side which is the west side. The address is 82990 Overseas Hwy or 82990 US 1, Islamorada, FL 33036. The 82 tells me the museum is north of mile marker 82. The 990 tells me it is very close to mile marker 83. In fact, The MM is at the north entrance to the parking lot. The John Pennekamp Coral Reef State Park in Key Largo is at MM 102.6. To find the distance between the two just subtract 83 from 102.6.


If you always wanted to snorkel or are an advanced scuba diver, Key Largo and the Upper Keys are calling you. Start planning your trip now!

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