There is precious little fresh surface water in the Florida Keys, but Big Pine Key is one of the places it exists.
That’s thanks to the Swiss-cheese nature of karst bedrock found in the limestone reef rock of the Keys, which stores rainwater in crevices and holes.
A bounty of fresh water is what helps support the population of Key deer and other wildlife in the Lower Keys.
On Big Pine Key, Blue Hole is the largest natural freshwater source in the KeysFound nowhere else on Earth, the Key deer is the world’s smallest deer. Grown bucks may be no taller than a German shepherd.
In 1957, only 50 Key deer remained. To prevent species extinction, 84,351 acres on Big Pine Key and on 24 other nearby islands was permanently protected as National Key Deer Refuge.
Refuge kiosk at Wildlife TrailsResources

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Overview
Location: Big Pine Key and surrounding islands
Visitor Center: 24.670391, -81.35443
Address: 30587 Overseas Hwy, Big Pine Key
Fees: Free
Restroom: At the visitor center
Land manager: National Key Deer Refuge
Phone: 305-872-0774
The refuge is open daily from a half hour before sunrise to a half hour after sunset. Visitor center open 10-3 Wed-Sat.
All areas are day use only. For your safety, stay on established trails. Insect repellent is a must.
Report wildlife emergencies such as injured or dead Key deer or aggressive animals to Florida FWC immediately at 888-404-3922; press Monroe County extension.
Directions
The visitor center is on the bay side of US 1 on Big Pine Key at mile 30.5, north of Key Deer Blvd.
About the Refuge
The Key deer population has rebounded to nearly a thousand deer. They roam through the populated areas of Big Pine Key as well as through the woods.
There are three nature trails along Key Deer Blvd on Big Pine Key where these diminutive deer are frequently seen. The most likely place to see them is at Blue Hole.
Blue Hole For the easiest wildlife watching at National Key Deer Refuge, visit the trail and observation deck at Blue Hole, a cenote-like pond that is the largest body of fresh water in the Florida Keys.
Key deer doe emerging from the forest at Blue HoleA little farther up the road, the Wildlife Trails lead into natural pine rocklands and rockland tropical hammock habitats where Key deer forage.
Fredrick C. Mannillo Jr. Nature Trail Key deer browse the understory of a pine rockland explored on this short accessible interpretive trail within National Key Deer Refuge.
Jack C. Watson Wildlife Trail Rare pine rockland and rockland tropical hammock are key habitats for Key deer along this immersive interpretive loop on Big Pine Key.
Key deer in the underbrush along the Mannillo TrailStick to established trails in National Key Deer Refuge. There are a large number of poisonwood trees and some manchineel trees in these rare rockland habitats.
Both native trees have highly toxic leaves and bark, and their fruits are deadly to humans. Leaving the trail puts you at risk of brushing into them.
Poisonwood predominates in the pine rocklands understoryWhile developed trails are on Big Pine Key, old roads into the preserve can be followed at several other locations.
These public access points are on Big Pine Key, No Name Key, and the Sugarloaf Keys. Ask Visitor Center staff for a map of the outlying trails.
Pine rocklands habitatWe detailed most of these remote trails in 50 Hikes in South Florida. Of them, the Long Beach Trail has since been abandoned.
It sustained significant hurricane damage and will not reopen, although you are permitted to walk down the shoreline.
Long BeachOf course, you may see Key deer wandering around anywhere on Big Pine Key, No Name Key, and the neighboring islands.
Tiered speed limits are in effect on all roads with lower speeds after dark. Please drive with caution through Key deer habitat.
Please do not feed the deer, as they lose their natural fear of humans and put themselves at danger.
This buck approached us in the parking lot of Tom Thumb, so we know it’s been fed.Trail Map

Related Articles
The Future of Florida’s Key Deer (8/21/2019) A public meeting by the U.S. Fish & Wildlife Service on August 22, 2019 is the first step in informing the public of the potential of Key deer being removed from the Endangered Species List.Explore More!
Slideshow
See our photos of National Key Deer Refuge
Nearby Adventures
Overseas Heritage Trail, Lower Keys 38.0 miles. Between Key West and Bahia Honda Key, this segment of the Florida Keys Overseas Heritage Trail crosses many historic railroad bridges along mangrove-lined shores.
Bahia Honda State Park Long known for its beaches, Bahia Honda State Park provides a slender ribbon of Atlantic oceanfront amid a natural tropical setting in the lower Florida Keys.
Key West Tropical Forest & Botanical Garden Boardwalks and footpaths wind through curated plant collections against a backdrop of natural habitats at the Key West Tropical Forest & Botanical Garden.
Sonny McCoy Indigenous Park Within sight of the Atlantic Ocean, Sonny McCoy Indigenous Park is a rare patch of green space in the city of Key West, with native trees and a natural freshwater pond.- Baseline Trails - November 7, 2026
- Hal Scott Yellow Trail - November 3, 2026
- Hal Scott Preserve - October 28, 2026

