7/20/15 UPDATE: Portions of Fort Drum Marsh are closed because of the unfunded need for St. Johns Water Management District to rebuild a bridge.

It’s the birthplace of the St. Johns River, a mosaic of wet prairies, cypress swamps, and hardwood hammocks in the wide open spaces of Indian River County, waiting for you to explore. Fort Drum Marsh Conservation Area covers more than 20,000 acres, but this hike zeroes in on 3 miles in two loops on the high ground – around Horseshoe Lake and Hog Island – near Yeehaw Junction.
Resources

Overview
Location: Yeehaw Junction
Length: 3 miles
Lat-Long: 27.613700, -80.757083
Type: Loop and round-trip
Fees / Permits: none
Difficulty: moderate to difficult
Bug factor: moderate to annoying
Restroom: Yes
Rains may cause parts of the trail on Hog Island to flood, making parts of your walk more of a wade, thus the “difficult” rating – along with the scrambles you’ll do around Horseshoe Lake. The campsite tends to stay dry.
This is an active hunting area; check the information at the Florida Fish & Wildlife Conservation Commission for Fort Drum Marsh WMA before making plans to hike or camp.
Directions
Drive either 10 miles east on SR 60 from the Yeehaw Junction exit of the Florida Turnpike, or 15 miles west on SR 60 from I-95 exit 147, Vero Beach. The entrance to Fort Drum Marsh Conservation Area lies to the south; look for the small sign. Follow the road along the levees for 0.8 miles to reach the parking area at Lake Cara. An attendant may be present. Open the gate in front of you (and close it behind you) to drive another 1.3 miles on a narrow limestone road to reach the Horseshoe Lake parking area. If the Lake Cara gate is locked, walk south down the road from the Lake Cara parking lot, extending the total length of your hike to 5.6 miles.
Hike
As you drive into the preserve, watch for caracara. These unusual looking birds are Mexico’s equivalent of our American bald eagle, their national symbol. They have dark feathers and a parrot-like face, and are often seen hopping around along the ground. Your hike starts at the Horseshoe Lake parking area, and encompasses two interconnected trails—the 1-mile Horseshoe Lake Trail and the 2-mile Hog Island Trail.
From the Horseshoe Lake parking area, start your hike by taking a left past the picnic pavilion. Sign in at the hiker register, and begin the counter-clockwise loop around the lake atop marl-and-shell spoil piles covered in wispy muhly grass. When you come to a bridge, turn right to walk out and explore the island. There is a primitive campsite on the island, surrounded by your own personal moat. Returning to the main trail, turn right. Where the trail meets a fence line, turn left. The blazes change from white to blue.
It’s here you get into the heart of the hike—the walk to and around Hog Island, a dry hammock on the western edge of Fort Drum Marsh. Sloughs parallel both sides of this broad, sunny jeep road, providing you the chance to watch for waterfowl and alligators. At the fork in the jeep road, stay to the right. The trail gets a bit grassy and unkempt. A dense cypress swamp stretches off as far as the eye can see on the left, receding into darkness.
When you come to a boardwalk at 0.9 mile, turn left. The boardwalk is your bridge over to the dry ground of Hog Island. Around you, young bald cypresses rise tall and straight, their shaggy gray bark ringed with high water marks. Sunlight filters through the forest, illuminating the leaf-covered bottom of the shallow swamp through water tinged the color of tea. At the end of the boardwalk, turn right to follow the orange blazes around the perimeter of Hog Island. The trail may be damp in places. Keep alert for blazes as the trail frequently zigzags.
After 1.7 miles, two poles in a clearing indicate a junction of trails. A cross-trail takes off to the right, marked with white blazes. Turn left, following the yellow blazes of the outer loop underneath a forest of low live oaks into a mixed hammock of pines and palms. Cypress knees poke through the footpath, which gets dark and squishy underfoot. At 2.3 miles, a blue-blazed trail to the left leads to the backpacker’s campsite. A thick bed of pine needles provides a natural mattress for your tent. At 2.4 miles, you return to the end of the yellow-blazed loop. Turn right on the boardwalk to retrace your trek back to the parking area.