Parking
Use the shared Watson and Mannillo trailhead parking off Key Deer Boulevard, about a quarter mile north of Blue Hole. One visitor estimated roughly eight spaces; the official material does not list a capacity.
Overview
About Mannillo Trail
Why go
- A genuinely short walk to a freshwater wetland platform.
- Three benches and interpretive panels make it easy to pause.
Heads up
- The route is fully exposed to sun.
- Published distance descriptions do not use a clear round-trip convention.
Map & elevation
The route
Loading the Overseas Highway map
Full mapElevation3–10 ft
TrailheadWatson and Mannillo Nature Trails shared parking and kiosk, Key Deer Boulevard24.70933, -81.38246
Plan your hike
Before you go
Parking
Safety
3 active Overseas Highway alerts
- CautionCoastal flooding across the Florida KeysA Coastal Flood Warning remains in effect for the Upper Keys and Coastal Flood Advisories remain in effect for the Middle and Lower Keys until 5 a.m.Official details
- CautionNighttime lane closures on Seven Mile BridgeExpect possible nighttime lane closures on Seven Mile Bridge for FDOT’s rehabilitation project to repair and strengthen the bridge.Official details
The highest, rockiest slopes around here are a summer buffet for grizzly bears.
Overseas Highway Tour Guide
Your drive to Mannillo Trail, narrated.
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
Blue Hole: A Freshwater Wildlife Stop0:00 / 0:36
“You’re nearing Blue Hole on Big Pine Key, a freshwater wildlife stop with a short, shaded path to a viewing platform.”
Plays as you drive up to this trailhead in the Parkwolf Overseas Highway Tour Guide.
More stories near here in the app
- Buttonwood Trail: Big Pine Key Wetlands
- No Name Pub: Pizza and Dollar Bills
- Salt on the Leaves
- Florida Keys Wildlife Refuges Nature Center
- 136 audio storiesacross Overseas Highway’s roads, triggered by GPS as you drive
- Wildlife heatmapsfor Crocodile, Alligator, Manatee, and 13 more
- Works offlinemaps, 26 trails, 88 places, and audio download before you lose signal
- CarPlay readysimple controls built for the drive
“Fantastic app with many points of information… It’s great to just turn on while you’re driving and it gives you an audio tour of the national Park. We love it!!!!”
Trail guide
Hiking Mannillo Trail
A short walk to the wetlandMannillo Trail is an easy out-and-back through pine rockland to a freshwater wetland platform.
Mannillo Trail is an easy out-and-back through pine rockland to a freshwater wetland platform. The mapped path is 0.13 to 0.14 mile each way, or about 0.26 mile round trip; some descriptions round it to 0.3. The refuge calls it an 800-foot out-and-back but does not clarify whether that includes both legs, so treat the total as an estimate. Allow about 15 minutes with a pause at the deck. This is a quick nature stop, not a substantial hike, and a Key deer sighting is never a sure thing.
Follow the limestone pathStart at the shared Watson and Mannillo parking off Key Deer Boulevard.
Start at the shared Watson and Mannillo parking off Key Deer Boulevard. The hardened limestone path crosses pine rockland in full sun, with three benches and interpretive signs before the wetland platform. Turn around there and retrace the route; the nearby Watson Trail is a separate two-thirds-mile loop.
Look into the limestoneRainwater collects in shallow solution holes in the old coral limestone.
Rainwater collects in shallow solution holes in the old coral limestone. Pink glades lobelia can grow around wet pockets, and ladder-brake fern in shaded holes. The trail honors local environmental advocate Fred Mannillo. At the deck, frame the pale limestone openings with palmettos behind them.
Plan for sun and rainCarry water and sun protection; summer mornings and late afternoons are the more comfortable…
Carry water and sun protection; summer mornings and late afternoons are the more comfortable times to visit. Parts of the refuge's trails can flood during rainy season, and mosquitoes can be a seasonal nuisance. Leashed pets are allowed, but bikes and motor vehicles are not. Refuge trails are open from 30 minutes before sunrise until 30 minutes after sunset. No food, restroom or drinking water was confirmed at the trailhead.
Wildlife
Wildlife in Overseas Highway
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.
