Key Largo Hammock Botanical State Park is truly a botanical treasure, with the highest concentration of champion trees in one place in the United States.
What’s even more surprising about this concentration of trees is that none are over 45 feet tall.
Discover the natural beauty of Key Largo Hammock on this round-trip walk to an overlook over an old quarry.
Tropical trees sport interesting patterns on their barkResources
Resources for exploring the area

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Overview
Location: Key Largo
Length: 1.1 mile round trip
Trailhead: 25.1761, -80.3695
Address: CR 905 & MM 106, Key Largo
Fees: $2.50 per person at honor box. Includes per-person Monroe County surcharge
Restroom: Composting toilet
Land Manager: Florida State Parks
Phone: 305-451-1202
Open 8 AM until sunset daily. Leashed pets and bicycles welcome.
Stay on the pathways! There are poisonwood and machineel trees throughout the hammock, both of which can cause severe reactions for anyone allergic to poison ivy.
Expect insects no matter the time of year. Always use mosquito repellent. During the summer months insects can be extreme. As this is a botanical state park, no mosquito control spraying is done here, unlike throughout most of the Florida Keys.
Directions
Driving north on US 1 from John Pennekamp Coral Reef State Park, keep right at the fork for SR 905 (to Card Sound Rd). The trailhead parking area is on the right after 0.5 mile, in front of a large archway.
Hike
Park next to the archway and follow the pavement into the woods. It doesn’t look like a trail at all.
In fact, it’s the old paved access road to Port Bougainville, and is open to bicycles as the Port Bougainville Trail.
Plaque honoring Anna Dagny JohnsonLignumvitae trees flank the front entrance. Listen for the rustle of palm fronds overhead, and look up: endangered white-crowned pigeons nestle in the tree tops.
As you walk along the ribbon of pavement, look into the forest, not at the trail. Identification tags help you pick out trees from the jumbled thicket.
Watch for the interpretive signs on the sidesThe trail curves past a composting privy, and comes to a junction with a picnic shelter in the middle.
This is the beginning of the big loop on the Port Bougainville Trail. Turn right.
Picnic area at trail junctionPay attention to the plant identifications and notice the subtle differences between the various trees, which blend together to form a thick green screen on both sides of the old road.
Not far off into the woods are the grand champion roughleaf velvetseed and boxleaf stopper, at 17 feet and 19 feet, respectively.
One of the markers pointing out specific tropical speciesOf the all of the grand champion trees in the hammock, few of them reach 30 feet tall—the 34-foot blolly being a notable exception.
As you walk past a bench to the start of a stone wall on the left, watch for a break in the wall.
Gap in the wallAfter 0.3 mile, turn left at the “Nature Trail” sign and follow the narrow footpath into the cool deep shade of the forest.
At the fork, keep left, walking past a number of small trees with interpretive markers. As the trail curves to the right, it comes out into an open, disturbed area on the edge of the forest.
Dense tropical understoryAt a half mile, walk down the short spur trail for a sweeping view of the water, on the edge of a quarry created during the building of Port Bougainville.
On the far side, wild cotton fills a man-made ravine. Considered the scourge of the agricultural industry in 1932, South Florida’s wild cotton harbored pink boll worms.
Wild cotton growing along a quarryThe U.S. Department of Agriculture assumed would infect domestic cotton crops, and paid people to rip it out of South Florida woodlands.
Now, in an ironic touch, it’s protected, and listed as one of Florida’s most endangered species. With showy creamy yellow flowers and fluffy cotton balls, it’s a beautiful shrub.
Interpretation along the trailRetrace your steps back to the footpath and turn left. Make a right into the shady hammock at the four-way junction to complete the loop.
When you emerge at the bench, turn left to parallel the wall back down to the pavement. When you reach the pavement, turn right.
Nature Trail along rock wallTurn right again at the T intersection. West Indian mahoganies form mushroom-like canopies overhead. It only takes a few moments to return to the “Nature Trail” sign.
Continue down the pavement, looking carefully at the parts of the forest that you haven’t yet seen.
Dense tropical forestAlong with the mahoganies, gumbo limbo and poisonwood trees are the true giants, the high canopy of the hammock.
But the thickets still guard their treasures: milkbark and red stopper, limber caper and saffron plum, a parade of tropical species like no other on this continent.
Wild allamanda (Pentalinon luteum) seen hereContinue past the picnic area, turning left off the Port Bougainville Trail.
Pay attention to the smooth bark of the trees around you, where five different colorful varieties of the Florida tree snail, liguus, slip along slurping up algae and lichens.
A liguus snail in this tropical forestJamaican dogwood and satinleaf often seem to be a favorite perch for the liguus snails. There is a satinleaf in the butterfly garden.
Follow the old road back out to the parking lot to complete your 1.1-mile walk.
A satinleaf tree dominates the garden at the picnic areaTrail Map

Explore More!
Learn more about Dagny Johnson Key Largo Hammock Botanical State Park
Dagny Johnson Key Largo Hammock Botanical State Park A botanical treasure rescued from developers, Dagny Johnson Key Largo Hammock Botanical State Park has the highest concentration of National Champion trees in the United States
Port Bougainville Trail At Dagny Johnson Key Largo Hammock Botanical State Park, enjoy the island's bounty of National Champion tropical trees from the 2.4 mile loop of the Port Bougainville TrailSlideshow
See our photos of Key Largo Hammock
Nearby Adventures
More worth exploring while you’re in this area.
Crocodile Lake National Wildlife Refuge Protecting more than 6,700 acres of Key Largo to provide prime habitat for the endangered American crocodile, Crocodile Lake NWR has a small visitor complex where you can learn about species conservation at the refuge.
Pennekamp Grove Trail If you've ever wondered where Key limes came from, take a walk on the 0.5-mile Grove Trail at John Pennekamp Coral Reef State Park to see of one of the historic groves of Key Largo.
Florida Keys Overseas Heritage Trail Spanning from Key West to Key Largo, this 108-mile linear state park corridor is an island-hopping slice of tropical paradise along the former route of the Florida Overseas Railroad.
Pennekamp Wild Tamarind Trail Tunneling into the deep shade of the Key Largo Hammock, the Wild Tamarind Trail provides a close-up look at a not-so-common forest. Official Website
- Hal Scott Yellow Trail - November 3, 2026
- Hal Scott Preserve - October 28, 2026
- Tradewinds Park - October 27, 2026

