John Pennekamp Coral Reef State Park: Everything to Know Before You Go

In 1960, a stretch of ocean off Key Largo became the first undersea park in the United States. John Pennekamp Coral Reef State Park — named for the Miami newspaper editor who fought for it — protects roughly 70 nautical square miles of coral reef, seagrass beds and mangrove swamp, including the only living coral reef in the continental US. It is, by any measure, the reason to come to Key Largo.

What's actually in the park

Think of Pennekamp as two parks. Onshore, at Mile Marker 102.5, there's a compact state park with two small man-made beaches (Cannon Beach and Far Beach), mangrove trails, an aquarium-equipped visitor center, kayak and paddleboard rentals, and a concession store with wraps, sandwiches, ice cream and cold drinks. Offshore is the main event: miles of protected reef line with names like Molasses Reef, Grecian Rocks and Dry Rocks — home of the Christ of the Abyss statue.

The four ways to do the reef

Snorkel. The park's reefs are shallow, calm and beginner-friendly — the best snorkeling in the Keys. Boat trips run morning and afternoon; our 2-hour snorkeling adventure includes gear, instruction and bottled water. The full first-timer rundown is in our Key Largo snorkeling guide.

Glass-bottom boat. The reef without the wetsuit — two and a half hours over the coral with narration, sea turtle sightings and a dry camera. See the glass-bottom boat guide.

Kayak or paddleboard. The mangrove channels behind the beaches are flat, sheltered and full of herons, rays and baby nurse sharks. Rentals run hourly; details in our kayaking guide.

Dive. Two-tank reef dives leave daily. Shallow profiles, warm water, huge visibility on good days — some of the easiest 'real' diving in the country.

Beaches: set expectations

Cannon Beach and Far Beach are small, calm and man-made — lovely for a swim and a picnic, with a replica Spanish shipwreck just off Cannon Beach that snorkelers can reach from shore. But nobody should come to Pennekamp expecting Miami Beach; the sand is a staging area, the reef is the show.

Getting there and getting in

The park entrance is at Mile Marker 102.5 on the Overseas Highway. Entry is a few dollars per person, boat tours are booked separately, and summer weekends can hit capacity by late morning — another argument for arriving early. If you're coming from Miami without a car, the Bayside Marketplace day trip drops you on the island with the whole day to work with; see how to visit without a car.

Make it a day

Morning reef trip, lunch at a waterfront fish house, afternoon kayak through the mangroves, sunset drink at a tiki dock — that's the classic Pennekamp day, and it fits comfortably inside the day trip from Miami. We've laid the whole thing out hour by hour in our one-day Key Largo itinerary.