Tucked in the lowlands of South Carolina, Congaree National Park is a lush, tangled wilderness of ancient trees and slow-moving, tea-colored waters. But for decades, much of this 22,000-acre expanse remained a mystery, even to those tasked with protecting it. Then came John Cely—a retired biologist, lifelong explorer, and the unlikely creator of what’s now considered the most accurate and beloved map of the park.
His creation, affectionately known as “The Cely Map,” is more than just a navigational tool. It’s a hand-drawn portrait of a landscape Cely has known intimately for over half a century. Where official maps fail to capture the nuance of Congaree’s dense swamps and hidden channels, Cely’s chart comes alive with detail—paths once used by loggers, ghostly hunting lodges, even the subtle scars left by wild boars and beavers.
A Swamp Called Home
Cely’s connection with the Congaree dates back to 1967, when he was a 17-year-old biology student at Clemson University. After writing a fan letter to local conservationist and journalist Harry Hampton, Cely was invited to explore the swamp. That visit changed his life. “That was a game changer,” he says in his gentle Southern drawl. “I’ve been in love with the place ever since.”
Over the years, Cely has played many roles: conservationist, bird biologist, Champion Tree hunter, tour guide. He participated in the grassroots movement that eventually led to the establishment of Congaree Swamp National Monument in 1976 and its elevation to national park status in 2003. He’s led bird surveys and educational walks and introduced countless visitors to the wonder of the swamp’s unique ecosystem. But even with all he had contributed, something still gnawed at him.
“I didn’t have much to justify all these years of knocking around this place except for photographs and old memories,” he said. “We needed a good map of the Congaree.”
The Problem with Mapping a Swamp
It’s not that maps of Congaree didn’t exist—they just weren’t especially useful. The flat floodplain lacks significant elevation or easily recognizable landmarks, making it extraordinarily difficult to map using conventional topographical techniques. As a result, most existing maps depicted the area as a vague green void, with trails and waterways fading into abstraction.
That wasn’t good enough for Cely.
Determined to document the real landscape, he began drawing by hand, starting with a traced outline of the park’s boundary from an aerial photo. Then, over the course of years, he filled in the gaps—using little more than a compass, his memory, and countless hours wandering the swamp on foot.
Much of what he added came straight from his own observations. The Cely Map is adorned with names he gave to the park’s obscure features—Scrubby Gut, Big Snake Slough, Horseshoe Pond—etched in meticulous black ink. He chronicled hurricane damage, noted the presence of rare trees, and recorded the ever-changing paths of water channels that appear only when the Congaree River floods in spring.
Mapping by Memory and Muscle
Creating the map wasn’t just a matter of artistry—it required incredible effort. Without GPS (still not widely used in the 1990s), Cely measured distances by pacing them out, step by step. He camped, hiked, and explored, often alone, guided by decades of familiarity with the terrain.
His work culminated in a four-by-two-foot map, completed around 2001. When he presented it to the park staff, they were thrilled. It was soon made available in the visitor center’s gift shop, sold alongside the official National Park Service map.
Cely was modest about his expectations. “I thought if I sold 50 maps, I’d be happy,” he recalls. Instead, it became a hit—with thousands sold and glowing endorsements from the people who know the park best: its rangers.
A Tool for Rangers, A Gift to Visitors
Park rangers and conservationists alike now rely on Cely’s creation. John Grego, president of the nonprofit Friends of Congaree Swamp, even cuts his copy into portable, pocket-sized pieces to use during his hikes. “Without John’s map,” he says, “you’re kind of just stumbling around.”
Even scientific evaluations have confirmed its precision. A recent lidar survey determined that Cely’s map features were accurate to within about 26 feet—a remarkable feat for something made without digital assistance.
“It’s a remarkable achievement,” says University of South Carolina geologist Raymond Torres. “The level of detail and the accurate placement of that information is altogether astounding.”
A Living Document
Cely’s map isn’t a static artifact. He continues to update it (the current version is 4.1), making changes after hurricanes, floods, or any noticeable shifts in the landscape. On his near-daily walks through the forest, he keeps an eye out for anything new.
Even after decades of exploration, Congaree still manages to surprise him. “As many times as I’ve been down there,” he says, “I still find something new every time I go.”
In a world increasingly defined by satellite imagery and AI-generated cartography, Cely’s work is a powerful reminder of what deep knowledge, patient observation, and human connection to place can achieve. His map doesn’t just show you where to go—it tells the story of a lifetime spent immersed in the wild, muddy heart of South Carolina.
And for every hiker, naturalist, or curious traveler trying to find their way through the maze of Congaree, it’s the best guide they could hope for.
