Miami to Key West: a 3-day Overseas Highway road trip

Why this itinerary skips Miami entirely

This is the compact version of the Overseas Highway run. It assumes you have already seen Miami and South Beach, or plan to see them on another trip — see the 7-day Miami and Florida Keys itinerary if you want both. Here, all three days go into the Keys themselves: Key Largo, Islamorada, Marathon and Key West, and nothing else.

Set expectations before you leave Miami International (MIA) or Fort Lauderdale-Hollywood (FLL): the drive down the US-1 and the Overseas Highway is roughly 160 miles (257 km) and takes 3.5 to 4 hours without stops, longer with Memorial Day or holiday traffic on the two-lane stretches. A car is not optional on this route — there is no train or bus network that covers Key Largo, Islamorada and Marathon the way Metrorail covers the city. Rent a car in Miami or Fort Lauderdale and plan to keep it for all three days; see renting a car in Miami, tolls and parking before you sign anything.

Because the itinerary is this tight, it skips detours off the highway. There is no time here for the Everglades, Biscayne National Park or a Bahamas day trip — those belong on longer trips. What follows is four stops in three days, each earning its place on the road.

Day 1: Miami to Marathon, with Key Largo and Islamorada on the way

Leave Miami early — by 8am if you can, to beat both traffic and the midday heat. The drive to Key Largo from Miami is about an hour, mostly on US-1.

Key Largo (roughly 9am to noon). This is the first of the Keys and the gateway to John Pennekamp Coral Reef State Park, the first undersea park in the United States. If snorkeling or diving is a priority for the trip, this is the spot: the reef here is more accessible than anything closer to Miami. Book ahead in winter (December to April), when the dry season brings the calmest water and the biggest crowds. See Key Largo snorkeling and diving for how the park’s boat trips compare to private operators.

a Key Largo sunset cruise is really an evening activity, so if you are only passing through at midday, save it for a return trip rather than trying to squeeze it in now.

Islamorada (roughly 1pm to 3:30pm). About 20 minutes south of Key Largo, Islamorada is built around sport fishing, and it shows: charter boats line the marinas, and Islamorada is a reasonable lunch stop with fresh seafood on both sides of the highway. If fishing interests you at all, this is the only point on the trip built for it — Marathon and Key West do not have the same charter density.

Marathon (arrive by late afternoon, stay overnight). Marathon sits roughly in the middle of the Keys and makes the most sense as a one-night stop, both for pacing and because it puts Key West within a shorter final drive the next morning (about an hour and 15 minutes). Marathon’s two landmarks are the Seven Mile Bridge — genuinely worth pulling over for, since the old bridge alongside the new one is open to walkers and cyclists — and the Turtle Hospital, a working rehabilitation center that runs guided tours explaining real turtle-conservation cases, not a roadside attraction dressed up as one.

In the evening, a lower-key option than a full charter is a tiki-style cruise: a tiki boat cruise around Marathon’s waterways, floating rather than driving, with music on board rather than a guided tour.

Day 2: Marathon exploring, then on to Key West

With Marathon as a base for the morning, this day has two shapes: stay slow in Marathon before pushing on, or leave earlier and give Key West a longer runway. Given how much there is to do in Key West on Day 3 alone, most people are better off treating Marathon as a half-day and reaching Key West by early afternoon.

Morning in Marathon. If you did not fit it in on Day 1, the Seven Mile Bridge walkway and the Turtle Hospital both work well before checkout. A boat option that suits a shorter morning window: a sandbar boat tour with lunch out of Marathon anchors in shallow water on Florida Bay rather than covering distance, so it fits a half-day without feeling rushed.

The drive to Key West (about 1 hour 15 minutes). This last stretch covers the most photographed miles of the Overseas Highway, including the older sections of the Seven Mile Bridge and several smaller island crossings. Fuel up before Marathon — gas stations thin out on the last leg, and Key West prices run higher than the mainland.

Afternoon and evening in Key West. Check in, then use the rest of the day to get oriented rather than trying to see everything at once: walk Duval Street, find the Southernmost Point buoy (it marks a symbolic spot, not literally the southernmost point of the continental United States, but it is the photo everyone takes), and end the day at Mallory Square for sunset — a nightly, informally organized gathering of street performers and vendors that has been a Key West ritual for decades. Reserve dinner ahead in high season; Key West’s small footprint means good restaurants fill early.

Day 3: Key West, then the drive back

This is the only full day dedicated to Key West itself, so plan it deliberately.

Morning. The Ernest Hemingway House, where the writer lived through much of the 1930s, is worth the entry fee for the house and grounds alone, cat colony included. Pair it with a walk through Old Town’s residential streets — quieter than Duval and where most of the island’s historic architecture actually is. For a different angle on the same history, see Key West history and ghost tours.

Midday to afternoon on the water. Key West’s reason for existing on this itinerary, beyond the town itself, is what’s offshore. Options scale from a couple of hours to a full day:

On-the-water option	Typical length	Best for
Sunset or harbor cruise	2 hours	First-time visitors, easy add-on
Snorkeling trip to the reef	3–4 hours	Anyone who skipped Key Largo’s reef
Party or tiki boat rental	2–4 hours	Groups wanting a self-directed afternoon
Dry Tortugas day trip	Full day	Only if you build an extra day around it — see below

If your afternoon is open, renting a tiki party boat around Key West’s harbor is a flexible way to spend a couple of hours on the water without committing a whole afternoon, and it works well as a lower-cost alternative to a full charter. For food between stops, Key West food and drink tours cover the island’s Cuban and Caribbean-influenced menu better than picking a restaurant at random on Duval Street.

One thing this 3-day version cannot fit in: Dry Tortugas National Park, about 70 miles further west and reachable only by the official park ferry, seaplane or an authorized charter — never by road, since the Overseas Highway ends at Key West. See the Dry Tortugas National Park guide if a future trip has a spare full day for it; trying to bolt it onto this itinerary just breaks the schedule.

Evening. A second sunset at Mallory Square, or, if you have already seen it once, a quieter spot away from the crowds along the waterfront. Sleep in Key West rather than starting the drive back that night — four hours of highway driving after dark, much of it on two-lane roads shared with local traffic, is not worth saving one hotel night.

The next morning: drive back to Miami. Budget the same 3.5 to 4 hours, plus fuel and food stops. Leaving by mid-morning gets you back to Miami or the airport by early afternoon.

What this trip does and does not include

• Includes: Key Largo’s reef, Islamorada’s fishing-town character, Marathon’s Seven Mile Bridge and Turtle Hospital, and a full day in Key West covering Duval Street, the Southernmost Point, Mallory Square sunset and the Hemingway House.
• Does not include: any Miami or South Beach sightseeing, the Everglades, Biscayne National Park, or the Dry Tortugas — all of which need their own day and, in the case of the Dry Tortugas, their own boat or flight.
• Requires a car for the entire trip. There is no realistic way to cover Key Largo, Islamorada and Marathon by bus in three days.

Costs and practical notes

Prices run in ranges and change by season; check the current rate on the GetYourGuide or Viator listing before booking. As a rough order of magnitude: boat tours and cruises in the Keys typically run from the low $60s for a shared sunset cruise to a few hundred dollars for a private charter for a small group. Hotel rates in Key West are consistently higher than in Marathon or Islamorada, and both are higher than mainland Florida rates. Displayed prices exclude tax; Florida’s state sales tax plus county surtaxes apply, and hotels add separate accommodation taxes on top — expect a noticeably higher total than the room rate alone. Tipping is expected, not optional, at 18–20% in restaurants and for boat crews and guides.

If your trip falls between June and November, note that this is Atlantic hurricane season, with a peak from August through October. That does not mean a storm is likely on any given date, but it is worth booking refundable accommodation and travel insurance for a Keys trip in those months — see Miami’s hurricane season guide for what that actually means for trip planning.

Miami to Key West road trip: frequently asked questions

Can you really do Miami to Key West and back in 3 days?

Yes, but only by keeping the entire three days on the Overseas Highway itself, with stops in Key Largo, Islamorada and Marathon on the way down and a full day in Key West before driving back. There is no room in this version for Miami sightseeing before or after.

Do you need a car for this itinerary?

Yes, for all three days. Key Largo, Islamorada and Marathon are not connected by any public transit useful for this trip, and the Overseas Highway is the only road linking them to Key West.

How long is the drive from Miami to Key West?

About 160 miles (257 km), taking 3.5 to 4 hours without stops on the US-1 and the Overseas Highway. Traffic on the two-lane sections, especially around Islamorada and Marathon, can add significant time on weekends and holidays.

Should I stay overnight in Marathon or push straight through to Key West?

Staying overnight in Marathon splits the drive in two and leaves a full day free in Key West on Day 3. Pushing straight through on Day 1 is possible but leaves less time for Key Largo and Islamorada along the way.

Can I fit the Dry Tortugas into this trip?

No. The Dry Tortugas are about 70 miles beyond Key West, reachable only by an official ferry, seaplane or authorized charter — never by road — and need a full separate day of their own.

Is this itinerary different from a one-day Key West trip from Miami?

Yes, significantly. A one-day trip from Miami to Key West means roughly 7 to 8 hours of driving for a few hours on the ground. This 3-day version spreads the same distance across stops in Key Largo, Islamorada and Marathon, with a full day and an overnight in Key West itself. See Key West as a day trip versus staying overnight for that comparison in more detail.

What’s the best time of year for this trip?

The dry season, roughly November through April, brings calmer water, less humidity and clearer conditions for snorkeling and diving, but also the highest prices. The wet season (May to October) is cheaper and quieter but brings afternoon storms and, from June through November, hurricane season.