You’re basically going to the end of the world. Or at least, the end of the United States. Driving the Overseas Highway is a rite of passage, but honestly, most people mess it up by treating it like a standard interstate sprint. It’s not. If you’re looking for directions to Key West Florida, you aren’t just looking for a line on a map; you’re looking for a strategy to navigate 113 miles of bridges and narrow pavement that can turn from a dream into a parking lot in about six seconds.
The Overseas Highway, or U.S. 1, is the only way in and the only way out.
It starts in Florida City. From there, you have two choices: the "18-Mile Stretch" or Card Sound Road. Most GPS units will scream at you to take the Stretch because it’s faster. It’s a straight shot through the Everglades. But if there’s a wreck? You’re stuck. Card Sound Road costs a few bucks in tolls (it’s all electronic now, so have your SunPass ready), but it takes you through Alabama Jack’s, a dive bar where the conch fritters are actually worth the detour.
Navigating the Mile Markers
Once you hit Key Largo, throw your traditional sense of North and South out the window. Everything in the Keys is dictated by Mile Markers (MM). The numbers start at MM 127 in Florida City and count down to MM 0 in Key West. If you tell a local you're looking for a hotel on "the left side of the street," they’ll stare at you blankly. You need to know if it’s "Ocean Side" or "Gulf Side."
Florida Department of Transportation (FDOT) maintains this corridor with a level of intensity usually reserved for lunar landings. Why? Because the environment is brutal. Salt air eats bridges.
The Mid-Keys Bottleneck
When you’re following directions to Key West Florida, the real test of patience begins around Islamorada. This is the "Sport Fishing Capital of the World," and on weekends, the boat trailers are everywhere. Traffic here crawls. You’ll pass the Theater of the Sea (MM 84), and if you aren’t careful, you’ll spend forty minutes looking at their sign because of a local delivery truck blocking the lane.
The speed limits fluctuate wildly. 45 mph. 35 mph. 55 mph. Then back to 35.
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Monroe County Sheriff’s deputies do not play around. They know tourists are in a hurry to get to the Green Parrot Bar, and they’ll happily write you a ticket at MM 70 to slow you down. The road narrows. It becomes a two-lane highway for the vast majority of the trip. Passing is limited. You’re stuck behind a rental RV doing 10 under the limit? That’s your life now. Breathe in the salt air.
The Seven Mile Bridge: The Point of No Return
This is the peak of the drive. It’s located at MM 47.
To your left, the Atlantic. To your right, the Gulf of Mexico. It feels like you’re flying over the water. There is no shoulder here. If your car breaks down on the Seven Mile Bridge, you are effectively a maritime obstacle. Make sure your tires are aired up and your cooling system is solid before you leave Marathon.
Interestingly, you’ll see the old bridge running parallel to the new one. That’s Henry Flagler’s original railroad bridge, partially destroyed by the Labor Day Hurricane of 1935. It’s a ghost of Gilded Age ambition. People walk and bike the first section of it out to Pigeon Key, but for drivers, it’s just a massive, beautiful concrete reminder that the ocean eventually wins every fight.
Big Pine and the Deer
After the bridge, you hit Big Pine Key. The speed limit drops to 45 mph during the day and a strictly enforced 35 mph at night. This is to protect the Key Deer—tiny, endangered deer that are roughly the size of a large dog. They have zero fear of cars. If you hit one, not only is it a tragedy for biodiversity, but it’s a massive legal headache.
The directions to Key West Florida at this stage become a game of vigilance. The landscape changes here. It gets scrubbier. Less manicured. You’re entering the Lower Keys, which have a completely different vibe than the tourist-heavy "Upper Keys."
Arrival and the MM 0 Reality Check
As you approach MM 5, the road widens. You’ll see the Key West Tropical Forest & Botanical Garden. You’re close. But here is where the Google Maps "arrival time" lies to you.
The entrance to Key West involves a fork in the road. Most visitors take the right fork toward North Roosevelt Boulevard. This takes you past the "big box" stores—Home Depot, Publix, the stuff you didn't come here to see. If you want the scenic route, stay left on South Roosevelt. It takes you along Smathers Beach. It’s longer, but you’ll actually see the ocean instead of a Walgreens parking lot.
Parking: The Silent Killer
You’ve followed the directions to Key West Florida perfectly. You’ve reached the Southernmost Point buoy. Now, you want to park.
Good luck.
Old Town Key West was built for horses and pedestrians, not Suburbans. Street parking is mostly "Residential Only," and they will tow you. Use the ParkMan or Passport apps. Better yet, find a paid lot like the one at the Truman Waterfront or the Old Town Garage at Grinnell and Caroline Streets. Expect to pay $40 a day. Honestly, once you’re in, just ditch the car. Rent a bicycle. The island is only 2 by 4 miles. Driving a car in Key West is like trying to navigate a bathtub in a cruise ship.
What Most Guides Forget to Mention
- Fuel Strategy: Gas prices in the Keys are a heist. Fill up in Florida City or Homestead before you hit the Stretch. If you must buy gas in the Keys, Marathon usually has the most competitive prices because it's a "real" town where locals live and work.
- The "Sun in Your Eyes" Factor: If you’re driving down in the late afternoon, you are driving directly into the sun. It reflects off the water. It’s blinding. Polarized sunglasses aren't a fashion choice here; they are safety equipment.
- Friday/Sunday Congestion: Do not drive south on a Friday afternoon. Do not drive north on a Sunday afternoon. You will sit in Islamorada for two hours. The "Keys Crawl" is real and it is soul-crushing.
- Weather Alerts: In the event of a tropical storm or hurricane, the Overseas Highway becomes an evacuation route. High-profile vehicles (RVs, trucks) get restricted on the bridges if winds hit 40+ mph.
Actionable Steps for Your Trip
- Check the "Monroe County Traffic" Facebook groups or local radio (US 1 Radio 104.1) before you cross the 18-Mile Stretch. If there’s a "Signal 4" (accident), take Card Sound Road instead.
- Download offline maps. Cell service is generally good, but there are dead zones near the uninhabited keys where Spotify will cut out and your GPS might lag.
- Stop at Robbie’s of Islamorada (MM 77). Yes, it’s a tourist trap. But feeding the massive tarpon is a weirdly visceral experience that justifies the $5 entry fee.
- Watch your temp gauge. The heat in the Keys is relentless. An older car with a weak radiator will struggle in the stop-and-go traffic of the Upper Keys.
- Plan for four hours. Even though the mileage suggests a shorter trip from Miami, the reality of speed limits, boat trailers, and drawbridges (like the one at Snake Creek) means a four-hour window is much more realistic than two and a half.
Once you hit that "End of U.S. 1" sign, pull over safely, take your photo, and go find a slice of Key Lime pie that isn't neon green (real Key Lime pie is yellow). You’ve made it to the end of the road.
Keep your eyes on the mile markers and your foot off the gas. The island isn't going anywhere.