Florida Peninsula

The Overseas Highway

Flagler's railroad that went to sea

Open the interactive map →

Drive
Miami → Key West
Distance
~165 miles
Time
2–3 days
Highways
US 1 · Card Sound Rd
Avoids
nothing (there is only one road)
Region
Florida Peninsula

Henry Flagler spent his last fortune running a railroad across the ocean to Key West in 1912; the 1935 Labor Day hurricane, the strongest landfall ever recorded in the US, tore it apart and killed hundreds of veteran workers. The state paved the surviving bridges, and the result is the only road trip in America measured in mile markers to zero. Take Card Sound Road in, walk the old Seven Mile Bridge, and mind the tiny deer.

📍 Mile markers are the route's own numbering system; the Islamorada hurricane monument is the one that matters.

The drive, segment by segment

The 18-Mile Stretch

Miami → Key Largo · ~60 mi

Out of the city, through the mangrove causeway or the Card Sound alternate, into the dive capital of the upper Keys.

The Purple Isles

Key Largo → Marathon · ~55 mi

Islamorada's fishing fleet and hurricane monument, tarpon at Robbie's, and the turtle hospital at Marathon.

The Lower Keys

Marathon → Key West · ~50 mi

The Seven Mile Bridge, Bahia Honda's broken span, Key deer at dusk, and Mile Marker 0 at the end of the map.

Worth a detour

Spurs & side-roads

More back-roads routes

More in the Florida Peninsula: A1A: Flagler's Coast · The Space & Treasure Coast · Old Dixie: Cassadaga to Kissimmee · Cross Creek & the Springs · The Nature Coast · The Florida Cracker Trail · The Big Water · The Tamiami Trail

Browse all 85 routes → · Ready-made itineraries →