Key West City Guide
The Seven Mile Bridge: Driving & Walking the Overseas Highway
The Seven Mile Bridge is the iconic engineering centerpiece of the Florida Keys Overseas Highway, stretching for 6.79 miles (10.93 km) across open ocean between Knight's Key in Marathon (Mile Marker 47) and Little Duck Key (Mile Marker 40). Completed in 1982 to replace Henry Flagler's original 1912 railway bridge, the modern highway carries US-1 high over the boundary where the Gulf of Mexico meets the Atlantic Ocean. Running parallel to the modern highway is the famous 'Old Seven', whose eastern 2.2-mile section underwent a $44 million restoration, allowing visitors to walk, cycle, or take a scenic tram to historic Pigeon Key. The wider island directory and travel planner starts on the Key West City Guide homepage.
Quick answer Driving distance from Key West, walking the Old Bridge, and Pigeon Key
Read on 10 September 2026: The Seven Mile Bridge spans Mile Markers 40 to 47, a 55-minute drive from Key West. Driving across the modern highway is free. You can walk, run, or cycle the restored 2.2-mile historic Old Bridge from Marathon out to Pigeon Key (free pedestrian access, parking at MM 47). A small passenger tram also carries visitors to Pigeon Key for guided museum tours.
Key takeaways
- Drive time: approximately 50 to 60 minutes northeast of Key West along US-1.
- Old Bridge pedestrian trail: enter at Mile Marker 47 in Marathon; the 2.2-mile flat concrete path has shaded resting gazebos every half mile.
- Pigeon Key: an authentic 5-acre historic railroad worker settlement located beneath the bridge span, offering museum exhibits and snorkeling.
- Bring sun protection: there is zero canopy or shade along the 2.2-mile open-water bridge crossing; carry water and wear sunglasses.
Key facts
Opening hours
| Daily | Modern highway open 24/7; Old Bridge pedestrian path open daily sunrise to sunset |
|---|
Admission
- Adult
- Free highway drive and free pedestrian/bike path access ($0.00)
Planning it
- Time needed
- 1 to 2 hours for walking Old Bridge; 10 minutes to drive across
- Book ahead
- Recommended — a few days
- Address
- Mile Marker 40 to 47, Overseas Highway, Marathon, FL 33050
Driving and walking the bridge are free, while historic tours and passenger tram rides to Pigeon Key carry separate tickets:
Walk or bike the Old Bridge for free, or purchase the Pigeon Key museum tram package:
| Experience | Type | Highlights | Best For | Rate | Book |
|---|---|---|---|---|---|
| Old Bridge Pedestrian PathWalkers, runners, and cyclists crossing the restored 2.2-mile bridge trail | Public recreation | 2.2-mile pedestrian lane, marine wildlife spotting, ocean breezes | Walkers & cyclists | Free ($0.00) | Official site |
| Pigeon Key Tour & TramVisitors wanting a guided historical tour of the 1912 Flagler worker village on Pigeon Key | Guided tour & tram | Scenic passenger tram ride, 1912 historical worker cottages, museum tour | History lovers | $25.00 adult / $15.00 child | Official site |
| Conch Tour TrainKey West visitors wanting historical background on Flagler's railway without leaving Old Town | Narrated tram | Departs Key West; narrates Flagler's construction of the Overseas Railway | Key West sightseers | $42.95 | Check Availability |
Discover the engineering triumph of Henry Flagler's Overseas Railroad through guided tram tours.
from $42.95
Key West: Conch Tour Train 75-Minute Sightseeing Tour
The quintessential 75-minute loop through Old Town operating since 1958. Best for orientation and first-timers who prefer continuous live storytelling over walking in midday Florida heat.
Check Availability
from $48.50
Key West: Old Town Trolley 13-Stop Hop-On Hop-Off Tour
Full-day transport covering 13 stops across the entire island from Mallory Square to New Town. Ideal for travelers visiting Key West without a rental car or avoiding costly Old Town parking.
Check Availability
from $80.00
Key West: Guided Bicycle Tour with Cuban Coffee Tasting
The most intimate way to explore Old Town back lanes, smelling jasmine and frangipani blossoms while hearing stories of wreckers, sponge divers, and rum-runners from a resident guide.
Check AvailabilityPrices, ratings and details are the platform's own, checked in Q3 2026; dollar figures are the listed prices — the platform bills in your account's currency.
Flagler's Folly: constructing the 'Eighth Wonder of the World'
When standard oil partner Henry Morrison Flagler announced in 1905 his intention to build a 128-mile railway over open ocean to deep-water docks in Key West, critics ridiculed the proposal as 'Flagler's Folly'. Nowhere in the world had engineers attempted to sink hundreds of massive concrete bridge piers into open ocean tidal channels.
The Seven Mile Bridge was the project's most daunting segment. Over 4,000 workers—many recruited from New York and Europe—lived in temporary timber bunkhouses on Pigeon Key, battling clouds of mosquitoes, oppressive tropical heat, and violent hurricanes. Completed in 1912, the railway cut travel time from Miami to Key West to just four hours, earning the title 'The Eighth Wonder of the World'.
Walking or cycling the restored 2.2-mile Old Bridge
In January 2022, the Florida Department of Transportation completed a comprehensive $44 million structural restoration of the eastern 2.2-mile section of the Old Seven Mile Bridge, connecting Knight's Key in Marathon directly to Pigeon Key.
The roadway was stripped to its reinforced concrete deck, fitted with smooth safety railings, and outfitted with shaded resting pavilions. As you walk or pedal your bicycle high above the sparkling water, look down into the emerald shallows: giant stingrays, nurse sharks, schools of silver tarpon, and sea turtles are frequently visible swimming through the bridge pylons. The pedestrian path is open daily from sunrise to sunset.
Exploring historic Pigeon Key
Pigeon Key is a tiny 5-acre coral island situated directly beneath the center of the Old Seven Mile Bridge. Between 1908 and 1912, it housed over 400 construction workers, carpenters, and civil engineers working on the bridge foundation.
Today, the island is preserved as a National Historic Landmark containing eight historic yellow wooden buildings, including the original commissary, assistant foreman's quarters, and machine shops. Guided walking tours explain how workers survived devastating hurricanes and showcase early 20th-century diving gear and railroad artifacts. A charming solar-powered passenger tram operates regularly from the Marathon visitors center for guests who prefer not to walk the 2.2 miles.
Nearby Middle Keys stops
Combine the Seven Mile Bridge with these highlights in Marathon and Big Pine Key:
The Turtle Hospital
World-renowned sea turtle veterinary clinic and rehabilitation center in Marathon.
5 minutes drive east (MM 48.5)Bahia Honda State Park
Premier state park featuring Sandspur Beach, snorkel charters, and broken bridge trestle.
7 minutes drive west (MM 37)National Key Deer Refuge
Protected pine forest habitat of the miniature Key deer on Big Pine Key.
15 minutes drive west (MM 30)Frequently asked questions about the Seven Mile Bridge
How long does it take to drive across the Seven Mile Bridge?
Driving the modern highway bridge takes approximately 7 to 10 minutes at the posted 55 mph speed limit.
Is there a toll to drive across the Seven Mile Bridge?
No, there are no tolls anywhere along the Overseas Highway or the Seven Mile Bridge. Driving across is completely free.
Where do you park to walk the Old Seven Mile Bridge?
Park at the dedicated public parking lot at Mile Marker 47 on Knight's Key in Marathon (just before the start of the modern bridge). Parking is free.
Can you ride bikes on the Old Seven Mile Bridge?
Yes, bicycles, rollerblades, strollers, and pedestrians are all permitted on the restored 2.2-mile bridge trail.
Can you drive a car onto Pigeon Key?
No, private motor vehicles are not allowed on the Old Bridge or on Pigeon Key. Access is exclusively by walking, cycling, or taking the official Pigeon Key passenger tram.
Key West on video: Seven Mile Bridge
Verified video walkthroughs and footage of Seven Mile Bridge, providing visual perspective before your visit.
Coolest Road in America? - The 7 Mile Bridge in the Florida Keys
Walkthrough of Seven Mile Bridge by Backroad Driver.
Video: backroad driverDriving the Overseas Highway to Key West — Is It Really That Epic? 7 mile bridge
Walkthrough of Seven Mile Bridge by Dayle Travels.
Video: dayle travelsSeven Mile Bridge - Over the Ocean - Florida Keys - Florida - 4K Infrastructure Drive
Walkthrough of Seven Mile Bridge by Mileage Mike Travels.
Video: mileage mike travelsReviewed Q3 2026 (July–September 2026); next review Q4 2026. Prices, hours and terms are set by the venue or operator and confirmed at checkout.
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