Parking
Use the main parking area at Windley Key Fossil Reef Geological State Park, 84900 Overseas Highway (Mile Marker 85.5). Walk to the Alison Fahrer Environmental Education Center; the red route access is on the rock ledge behind it.

Overseas Highway, FL
A tiny loop through fossil coral and old quarry walls.
Overview
Map & elevation
Plan your hike

The highest, rockiest slopes around here are a summer buffet for grizzly bears.
Overseas Highway Tour Guide
Parkwolf is a GPS audio tour guide for Overseas Highway. As you drive, it chimes in with what’s ahead: hidden gems, upcoming stops, history, geology, and wildlife, right through your car’s speakers.
See the Overseas Highway audio tourRecorded for this trailhead
Windley Key: A Reef Inside a Quarry“You're coming up on Windley Key Fossil Reef Geological State Park, where quarrying exposed an ancient coral reef.”
Plays as you drive up to this trailhead in the Parkwolf Overseas Highway Tour Guide.
More stories near here in the app
Trail guide
Quarry Walls Walk is the red loop around Windley Quarry at Windley Key Fossil Reef Geological State Park. The official figure is 1/8 mile for the loop itself. Starting from the visitor-center end of the mapped connector and retracing it after the circuit makes the complete walk about 0.16 mile. Allow roughly 20 minutes if you want to stop and study the rock. This is a brief geology stop, not a long hike; come for the reef exposed by quarrying.
The cut limestone walls rise as high as eight feet and expose cross-sections of ancient coral. Numbered trail markers correspond to the park guide; it points out coral forms and smooth holes left by an ancient mussel. Pick up the guide at the education center before setting out. For a photo, move in close to one cross-section: the coral pattern is the memorable part, more than another wide shot of the quarry floor.
This is fossilized Key Largo limestone from a reef formed nearly 125,000 years ago. The Florida East Coast Railway bought Windley Key land for $852.80 in 1908, and quarry stone went into the Overseas Railroad's bed and bridge approaches. Later, polished decorative stone from the quarry was sold as keystone; quarrying continued into the 1960s. A short circuit here brings both the geology and the railroad story into view.
Park at the main visitor-center area and follow the red markers to the loop behind the Alison Fahrer Environmental Education Center. Stay with the red Quarry Walls Walk: the park has several nearby trails, and longer descriptions that combine this circuit with the separate Windley Trail refer to a different route. The park offers a powered Action Trackchair for its trails and quarries at no extra cost with park entry; ask the education center whether it suits this route. Pet access is limited to designated areas, and the park material does not say whether this loop is one of them, so check before bringing a dog.
Wildlife
18 sightingsCrocodileMost seen around 6 PMSighting map
255 sightingsAlligatorMost seen around 6 PMSighting map
55 sightingsManateeMost seen around 7 AMSighting map
70 sightingsCommon Bottlenose DolphinMost seen around 9 AMSighting map
51 sightingsBald EagleMost seen around 8 AMSighting map
1,120 sightingsKey DeerMost seen around 6 PMSighting mapSighting maps show where each species has been reported across Overseas Highway. Wildlife moves, so no sighting is guaranteed.
Keep exploring
EasyFlagler Quarry Trail0.2 mi · 20 min · At the trailheadA short loop through fossil coral and railroad history.
EasyQuarry Station Trail0.1 mi · 12 min · At the trailheadRailroad ruins tucked into a quarry of fossil coral.
EasyWindley Trail0.3 mi · 18 min · 0.1 mi awayA short loop pairs mangrove roots with a walk through fossil reef.
EasyGreen Hammock Trail0.5 mi · 36 min · 0.1 mi awayAn old quarry hides inside this half-mile hammock loop.
EasyPlantation Hammock Preserve Loop0.5 mi · 24 min · 2 mi awayA shaded hammock loop reaches a bench overlooking Florida Bay.
EasyPlantation Tropical Preserve Nature Trail0.2 mi · 15 min · 5.3 mi awayA tiny walk through a rare patch of Florida Keys hammock.
Sight · At the trailheadWindley Key Fossil Reef Geological State ParkWalk through a quarry that laid bare a fossil coral reef.
Sight · 0.7 mi awayTheater of the SeaA few hours of close-range shows, a lagoon beach, and railroad history.
Sight · 1.7 mi awayRain Barrel VillageA giant lobster and shady garden paths make an easy highway break.
Sight · 1.9 mi awayFounders ParkA shallow bay beach sits beside courts, fields, and a full-size pool.
Sight · 2.1 mi awayHistory of Diving MuseumOld helmets and underwater machines make diving history tangible.
Sight · 2.8 mi awaySouthwinds ParkA brief stop for Islamorada’s fishing heritage.
Sight · 2.9 mi awayFlorida Keys History & Discovery CenterKeys history, reef tanks and films about the railroad and hurricane.
Restaurant · 3.1 mi awayLorelei Restaurant & Cabana BarA Florida Keys landmark for bayfront seafood and sunset views.Parkwolf’s Overseas Highway ranking