A morning on the Florida Overseas Heritage Trail
When Sarah from our BugBitten team rolled her hire bike out of a Key Largo motel car park at half past six on a Tuesday morning in late February, the sun was barely a suggestion above the Atlantic. The air smelled of salt and something faintly vegetal — mangrove, seagrass, the particular low-tide musk of shallow subtropical water. There was almost no traffic on US-1 yet, and the trail surface ahead of her gleamed like a grey ribbon pulled tight between two bodies of water she could barely tell apart in the early light. She clipped her water bottle into the cage, checked the gears (approximate, as advertised), and pushed off into a wind that was — blessedly — coming from behind.
By the time she hit Tavernier Creek Bridge, the sky had turned from grey-pink to a hard, clear blue, a great blue heron was standing perfectly still in six inches of water below the railing, and she had already understood what this trail actually is: not a cycle path so much as a slow, extended argument that the Florida Keys are stranger and more beautiful than most of mainland America will ever be.
That ride took her two and a half days. She covered 183 kilometres of largely flat asphalt, crossed dozens of bridges, ate too much conch fritter, drank nowhere near enough water, and arrived in Key West with sunburned forearms and an opinion that this is one of the most genuinely satisfying long-distance cycling routes in the United States. None of that experience required exceptional fitness, specialist equipment, or a particularly early alarm clock. It did require a reasonable tolerance for heat, an ability to read wind, and a willingness to spend some sections riding on a highway shoulder rather than a dedicated path.
This is that trail. Here is what you actually need to know.
What makes this route worth your time
The Florida Overseas Heritage Trail follows the general line of Henry Flagler's old Florida East Coast Railway, a feat of early twentieth-century engineering that drove iron rails down through the coral islands to Key West, completed in 1912. The railway was destroyed in the Labour Day Hurricane of 1935 and never rebuilt; the causeway and bridge infrastructure that replaced it eventually became US-1, and the trail you ride today exists partly because people had the good sense to convert former railway bridges and unused road shoulders into a dedicated corridor.
That history matters because it explains why the trail exists at all — and why it feels, in places, like you are riding through something that survived rather than something that was built for leisure. The bones of the route are old. The Seven Mile Bridge, which forms the trail's single most spectacular section, was preceded by its original railway counterpart, stretches of which you can still see running parallel as a ghost causeway, broken in places, gradually returning to the sea.
Beyond the engineering history, the ecological context is remarkable. The Keys sit at the northern edge of a reef system that is one of the most biodiverse in the Atlantic, a system significant enough to be recognised internationally for its natural values. The UNESCO World Heritage Centre provides context on how such ecosystems are assessed globally, and while the Florida Reef Tract is not itself inscribed on the UNESCO World Heritage List, the broader Everglades system — which feeds directly into the water you are riding over — has held that status since 1979. You are, in other words, cycling through the fringes of a globally significant natural environment, not merely a pretty stretch of coast.
How the area feels day to day
The Keys are not a quiet place in the conventional sense. US-1 — the Overseas Highway — is a constant presence, and even on dedicated trail sections you are generally aware of the road nearby. Large RVs and pickup trucks hauling boats make up a substantial proportion of the traffic, and the commercial strip development through Key Largo and Marathon is thoroughly American in its signage, its franchise food options, and its general indifference to subtlety.
And yet the water is always there, on both sides, doing something extraordinary to the quality of light. The Gulf of Mexico to the west runs shallower and calmer; the Atlantic to the east is deeper, darker, more restless. Depending on the time of day, the straits between keys will go from pewter to jade to a turquoise so saturated it looks digitally adjusted. Pelicans cruise at roughly handlebar height. Frigatebirds wheel in thermals above the bridges. Ospreys nest on channel markers and watch you pass with studied indifference.
The towns themselves are worth understanding. Key Largo is functional, the largest of the upper Keys settlements, with genuine infrastructure — supermarkets, bike shops, motels at several price points, proper cafes. Islamorada, about 30 kilometres south, has more of a fishing-lodge atmosphere, with a concentration of waterfront restaurants and bait shops that still feel like they belong to working fishermen rather than Instagram aesthetics. Marathon sits roughly midway and is the most utilitarian town on the route — not pretty, but well-stocked, a good place to eat properly and sleep cheaply. Key West, at the southern end, is its own thing entirely: part carnival, part history, part functioning city, deeply strange, genuinely entertaining.
What to actually do here
Ride the Seven Mile Bridge
This is not optional. The bridge connects Knight's Key to Little Duck Key and covers, as the name suggests, approximately seven miles of open water. From the saddle of a bicycle, the effect is something that photographs simply do not capture: you are riding between sky and sea with nothing structural in your peripheral vision, just the trail surface narrowing ahead of you to a distant point, the water on both sides moving in the early light, and whatever birds happen to be working the shallows below.
Allow extra time here. Stop at the small viewing platform roughly a third of the way across. Look at the old Flagler bridge running parallel, its sections broken and weathered, terns perched along the remnant concrete. Consider the absurdity of what you are doing and enjoy it.
Explore the smaller keys
The trail threads through keys with names that still have texture — Plantation Key, Windley Key, Grassy Key, Sugarloaf Key. Most visitors blow through these on their way to Key West, and that is a reasonable choice if time is short. But Grassy Key has a small dolphin research facility open to visitors, and Windley Key has a geological quarry site that exposes the fossilised coral stone — known as keystone — that underpins the entire island chain. These are short detours worth taking if your pace allows.
Snorkel off the keys
The trail itself is a riding route, but you are never far from water you can get into. John Pennekamp Coral Reef State Park at Key Largo is the obvious entry point for reef snorkelling — gear hire is available at the park, and the boat trips out to the coral are genuinely worthwhile. If you want more places in Key Largo to Key West that pair well with the ride, the park is the single most compelling addition to the route.
Key West itself
Arrive by late afternoon if possible, when the light on Duval Street is warm and the heat has fractionally reduced. Lock the bike up, walk the Old Town, eat stone crab somewhere that is not on the main tourist drag. Mallory Square at sunset is genuinely worth the crowds. The Key West cemetery, which is small and peculiar and full of eccentric epitaphs, is worth thirty minutes of anyone's time. The Hemingway house is touristy but the cats are real.
When to go and when to stay home
November through April is the window. Specifically, January through March represents the optimum — temperatures are in the mid-twenties Celsius most days, humidity is manageable, and the prevailing east-to-south-east wind remains broadly useful for the Key Largo to Key West direction.
By May, the heat is already building toward something that makes mid-afternoon riding genuinely unpleasant. June through September is hurricane season, and while the Keys do not get struck every year, the risk is real and the humidity in that period is relentless — think 90 percent at eight in the morning, climbing from there. October can be acceptable, particularly the second half of the month, but you are running against the statistical tail of storm season.
Weekends in season — particularly long weekends and the period around Christmas and New Year — are significantly busier than midweek. If you have the flexibility, Monday through Wednesday arrivals in Key West mean cheaper accommodation and less competition for trail space.
How to get there and nearby stops
Miami is the practical gateway. Miami International Airport is roughly 90 kilometres from the northern trailhead in Key Largo, and a hire car makes the shuttle straightforward. If you plan to ride one way only (the sensible approach — Key Largo to Key West, with the wind), you will need to either arrange a shuttle back or fly out of Key West Airport, which handles flights to Miami, Fort Lauderdale, and a handful of other Florida cities.
Bike hire in Key Largo is available through several operators; ask your motel or search in advance. Quality ranges considerably. Inspect each bike before paying — check the gears shift cleanly, the brakes have genuine purchase, and the saddle adjusts to your height. In Key West, hire is equally available and the same advice applies.
The trail itself is accessible at multiple points, so you do not have to do the full 183 kilometres in one go. Day rides from Key Largo to Islamorada (around 40 kilometres return) or out to the Seven Mile Bridge from Marathon (roughly 50 kilometres return) are achievable options for people with limited time or with children in tow.
For context, the Keys are not the only place BugBitten covers where wildlife and outdoor activity genuinely overlap — the experiences available here sit in interesting contrast to something like the Oregon Zoo, where the wildlife is deliberately concentrated and curated rather than encountered at random below a bridge at dawn.
The not-so-good bits
Let us be honest about a few things.
The dedicated trail is not continuous. There are sections — most notably around Marathon and some of the smaller keys — where the trail routes you onto the US-1 shoulder. These sections are rideable, and the shoulder is generally adequate, but they are not pleasant. Traffic moves fast, trucks are wide, and if you are riding with nervous cyclists or children, these sections require attention. The trail markers through these road sections can also be inconsistent; a GPS track loaded onto a cycling computer or phone is genuinely useful.
Shade is essentially absent on the bridges, moderately sparse everywhere else. If you are riding in February in mild conditions, this is fine. If you are riding in any month between May and October, the sun exposure across the open water sections is serious, and the bridges can feel punishing. Sunscreen, a cap, and arm sleeves are not optional gear.
Accommodation requires forward planning. The Keys have finite bed capacity and they fill early, particularly on weekends and during the winter season. Budget options exist but they book out; leaving accommodation to the last minute in high season is a reliable way to end up in a motel that is either very expensive or very questionable.
The trail is also genuinely popular, and on good-weather weekends the sections near Key West and near Key Largo attract recreational traffic — families on hire bikes, rollerbladers, pedestrians — that makes fast riding inappropriate. This is not a complaint exactly, but it does mean the experience is not that of a quiet wilderness route. It is a shared-use path through a heavily visited tourist region, and it feels like one.
Final word from the BugBitten team
The Florida Overseas Heritage Trail is one of those routes that earns its reputation honestly. The flat profile and paved surface mean it is accessible to almost any rider with a basic level of fitness, and the two-to-three-day pacing suits people who want to move without rushing. But what makes it genuinely memorable is simpler than any of that: you spend two and a half days riding over an ocean, in extraordinary light, through an environment that is old and ecologically significant and still partly wild, and the effort required is modest enough that you can actually pay attention to where you are.
It also pairs well with the Philadelphia Zoo style of thinking about travel — places where the encounter with the natural world is the point, not the backdrop. On the Seven Mile Bridge at 7 a.m. with pelicans in the air and the water green beneath you, the Keys deliver that in full.
Go in winter. Pack water obsessively. Inspect the hire bike before you ride it anywhere. Book your accommodation at least three weeks ahead if you are going in January or February. And start early — the first two hours of daylight on this trail are the best two hours, and it would be a shame to sleep through them.