Crossing 42 bridges over open ocean, Florida’s Overseas Highway gets wilder every mile

It’s America’s ultimate road trip

Most highways connect cities. This one connects islands.

The Overseas Highway runs 113 miles along U.S. Route 1 through the Florida Keys, from the southern tip of mainland Florida all the way down to Key West.

You cross 42 bridges over the Atlantic Ocean, Florida Bay and the Gulf of Mexico. Mile markers count down from 127 near Florida City to zero at the end of the road.

In 2009, the Federal Highway Administration gave it the All-American Road designation, the highest honor a U.S. road can receive. Florida had never had one before.

The drive south starts easy, but it gets wilder the farther you go.

A railroad tycoon built this route across open ocean

Before cars ever crossed these bridges, trains did.

Railroad tycoon Henry Flagler finished the Overseas Railroad in 1912, connecting mainland Florida to Key West across miles of open water. People called it the Eighth Wonder of the World.

Then a hurricane in 1935 tore most of it apart. Florida bought the railroad path for $640,000 and converted the bridges for cars.

The Overseas Highway opened on March 29, 1938, and you can still see old railroad remnants if you know where to look.

Key Largo sits on top of the only living reef in the continental U.S.

Key Largo is the first and largest island you hit on the drive south.

At Mile Marker 102.5, John Pennekamp Coral Reef State Park covers about 70 nautical square miles of protected ocean. It was the first undersea park in the country.

You can snorkel over colorful coral, ride a glass-bottom boat or kayak through mangrove trails. Inside, a visitor center has large saltwater aquariums and nature films.

Most people come for the water, but the tropical hammock walks on land are worth the stop too.

Divers find a sunken Navy ship and a statue on the ocean floor

The coral reefs off Key Largo belong to the only living coral barrier reef in the continental United States. Divers come here to visit Christ of the Deep, a famous statue sitting on the ocean floor.

Nearby, the USS Spiegel Grove, a 510-foot Navy ship, was sunk offshore to create an artificial reef. Five species of sea turtles swim through these waters.

If you stick to snorkeling, the shallow reef areas are full of tropical fish, sea fans and sponges just below the surface.

Hand-feed giant tarpon right off the dock at Robbie’s Marina

Islamorada is a chain of six islands in the Upper Keys, and locals call it the Sport-Fishing Capital of the World. At Robbie’s Marina near Mile Marker 77.5, you can hand-feed giant tarpon from the dock.

The Starck family has run this waterfront fishing camp since the 1940s.

Down the road, Theater of the Sea is the second oldest marine mammal facility in the world, where you can swim with dolphins and sea lions. The History of Diving Museum traces 3,000 years of underwater exploration.

Rescued sea turtles get a second chance at Mile Marker 50

Marathon sits in the Middle Keys near Mile Marker 50 and works as a central hub for travelers heading south. The Turtle Hospital has been rescuing, treating and releasing injured sea turtles here since 1986.

Guided tours run about 90 minutes and take you behind the scenes to the rehabilitation tanks and veterinary areas. Staff treat five species of turtles, most commonly for tumors, boat strikes and fishing line injuries.

Every dollar from admission goes directly to turtle care and conservation.

The Seven Mile Bridge rises above two oceans at once

The Seven Mile Bridge is the longest in the Florida Keys and one of the most photographed spots on the drive.

It actually stretches 6.79 miles, and the road rises in a sweeping arc above the point where the Atlantic Ocean meets the Gulf of Mexico. Water surrounds you on every side with no land in sight for most of the crossing.

Every April, about 1,500 runners race across it in the annual Seven Mile Bridge Run. The bridge also carries the aqueduct that supplies fresh water from the mainland to the Lower Keys.

Walk the old railroad bridge to a five-acre island frozen in time

The original Seven Mile Bridge, built between 1909 and 1912, still runs alongside the modern one. It sits on the National Register of Historic Places.

A 2.2-mile section reopened to pedestrians and cyclists in January 2022 after a full restoration.

At the end of the walking path sits Pigeon Key, a tiny five-acre island where up to 400 railroad workers once lived during construction. You can tour the old worker quarters and a small museum.

Near Mile Marker 41, an Australian pine nicknamed Fred the Tree has taken root in the crumbling old bridge.

The first beach ever rated number one in America is at Mile Marker 37

Bahia Honda State Park covers more than 500 acres in the Lower Keys at Mile Marker 37.

In 1992, Dr. Beach rated its shore the number one beach in the United States, the first Florida beach to earn that title. The park has three beaches: Sandspur, Loggerhead and Calusa, each facing different waters.

A nature trail leads to the top of the Old Bahia Honda Bridge with views of the island and open ocean. Birders come for the endangered white-crowned pigeon and more than 30 species of warblers during migration season.

The world’s smallest deer stand two feet tall and live on one island

Big Pine Key is home to the National Key Deer Refuge, established in 1957 to protect a deer you won’t find anywhere else on the planet. Key deer are the smallest subspecies of white-tailed deer.

Adults stand only 24 to 32 inches at the shoulder and weigh between 65 and 80 pounds. Their population dropped below 50 in the 1950s but has recovered to around 800 today.

The Blue Hole, an old limestone quarry filled with rainwater, is where you might spot them along with alligators. They are most active at dawn and dusk.

Mile Marker 0 puts you 90 miles from Cuba

Key West sits at Mile Marker 0, the southernmost point of the continental United States. The Southernmost Point Buoy, a colorful concrete marker, reminds you that Cuba is just 90 miles south.

Fort Zachary Taylor Historic State Park predates the Civil War and holds the largest collection of Civil War-era seacoast cannons in the country.

The park also has one of the best beaches in Key West, with snorkeling right off shore. Every evening, crowds fill Mallory Square for the sunset celebration with street performers, artists and food vendors.

Climb 88 steps in a lighthouse that has stood since 1848

Key West’s historic Old Town is compact enough to cover on foot, full of pastel-colored homes and tropical gardens.

The Key West Lighthouse, completed in 1848 after an earlier one was destroyed in 1846, has 88 steps leading to views of the whole island. The Truman Little White House served as President Harry Truman’s winter retreat.

The Florida Keys Eco-Discovery Center has free exhibits about the marine environment. Over on Duval Street, shops and cafes line the road from the Gulf to the Atlantic, about a mile end to end.

Drive the Overseas Highway through the Florida Keys

You pick up the Overseas Highway at Key Largo around Mile Marker 106 and follow U.S. Route 1 south to Key West at Mile Marker 0.

The full drive takes about four hours without stops, but most people spread it over two days or more. State parks along the route charge entrance fees, typically around $8 per vehicle.

Attractions like the Turtle Hospital and Pigeon Key fill up, so book ahead. Keep in mind that the highway is the only road in and out, so plan for traffic on busy weekends.

This article was created with AI assistance and human editing.

Read more from this brand:

• Every night in Key West, hundreds of strangers gather to clap at the sun
• This tiny Florida Keys island has three beaches, a climbable old railroad bridge, and once won best beach in America
• Florida’s Overseas Highway skips across 42 bridges with open ocean on both sides