Key Largo

For most divers, late spring through summer (May to August) offers the warmest water and the best odds of calm seas for reef and wreck trips. Expect sea temps around 27°C to 30°C and long, easy multilevel profiles. Winter (December to March) can still be excellent, especially for reef dives, but cold fronts can bring wind, chop, and cancellations. If you want fewer crowds with good water, aim for April or November and keep a backup list for windy days.

Snorkeling is best when the surface is flat and the sun is high. April through August usually gives warm water and more calm mornings, with visibility often around 15 m to 25 m after a few calm days. In winter, snorkeling can be great between fronts, but wind-driven chop is more common. Book morning departures, choose shallow sites like Grecian Rocks, and pack a rashguard for sun and seasonal stingers.

Key Largo has two main depth bands. The reefs and patch reefs in Hawk Channel are generally shallow, often starting in 5 m to 8 m and topping out around 18 m. That makes them ideal for long multilevel dives and snorkeling. The big wrecks sit deeper: plan for profiles down to about 40 m at the sand, with shallower superstructure higher up. Treat wreck days as advanced dives and follow the captain's brief on current and mooring lines.

Most visitors dive by booking a two-tank boat trip with a Key Largo operator. Expect an early check-in, a short ride to a mooring field, then a reef or wreck first dive, surface interval on the boat, and a second shallower site. Bring your certification card, logbook if you are doing advanced wrecks, and cash for tips. If you want a specific wreck, book multiple possible dates because conditions can force a reef substitution. Many shops offer full rentals and nitrox.

Recreational divers and snorkelers do not generally need a personal permit to enter the Florida Keys National Marine Sanctuary, but you must follow sanctuary rules. In Sanctuary Preservation Areas, fishing and collecting are prohibited, and coral contact is not allowed. Use mooring buoys when they are available and never anchor on coral. If you are entering John Pennekamp Coral Reef State Park by car, you will pay the state park entrance fee at the gate. Commercial activities are handled through operator permits.

Sanctuary Preservation Areas are designed to protect shallow reefs and separate uses. You can dive, snorkel, and boat there, but you cannot fish or collect marine life. Do not touch or stand on living or dead coral. Anchoring restrictions are strict: do not anchor on coral, and do not anchor when a mooring buoy is available. Bring excellent buoyancy and fin control, keep gear streamlined, and treat every photo as a no-touch shot. These rules are heavily enforced on popular Key Largo sites.

Sea temperatures in South Florida typically range from about 21°C in the coolest season to about 30°C in the warmest. Most divers are comfortable in a 3mm wetsuit in summer and early fall, while winter visitors often prefer a 5mm or a 3mm plus hooded vest for longer bottom times. If you run cold, prioritize a thicker suit for wreck days because depth and wind on the boat amplify chill. Bring a light rain layer for summer storms topside.

From Miami International Airport (MIA), Key Largo is a straight shot south on U.S. 1. Most travelers rent a car at the airport and plan for a 100 km drive to the Key Largo dive-marina area. There are also shared shuttles and private transfers, but having a car makes it much easier to reach different marinas, restaurants, and parks on the Upper Keys. If you are arriving late, pick up groceries on the mainland before crossing into the Keys, where options are smaller and prices higher.

Non-divers can fill a day in Key Largo without feeling like they are waiting around. John Pennekamp Coral Reef State Park has beaches, picnic areas, and mangrove paddling routes, and the REEF Ocean Exploration Center is a quick stop for reef science and exhibits. Bayside resorts and marinas are set up for sunset hangs over Florida Bay. If the group wants a shared adventure, consider a glass-bottom boat or a short snorkel trip where everyone can participate. For a full-day break, drive north toward the Everglades.

If you want to harvest spiny lobster, Florida requires a recreational saltwater fishing license and a lobster permit. The sport mini-season is the last consecutive Wednesday and Thursday of July each year, and Monroe County has special restrictions, including no night diving during the sport season. The regular season runs from early August through March, but harvest is still prohibited in no-take zones and many protected areas. Always measure carapace length and follow bag limits, and remember that many Key Largo signature reefs are SPAs where collecting is not allowed.

Visibility in Key Largo can be excellent, but it is weather-driven. After several calm days, reef sites can open up to 20 m or more, which is great for wide-angle reef scenery and statue shots. Wind, waves, and heavy rain can reduce visibility by stirring sand and pushing plankton. Winter often brings clearer water between fronts, while summer can be glassy and clear between thunderstorms. Photographers should book multiple days, start early, and keep a list of shallow backup sites like Pickles Reef for windy conditions.