On a wintry grey morning of 38 degrees, my new friend Rosemary Miller is waiting for me when I reach the Thomas Darling Preserve at Two-Mile Run. Managed by The Nature Conservancy, the preserve is 2,500 acres of spruce forest and an array of glacial wetlands — boreal bogs, conifer swamps and peat bogs — on top of Pocono Plateau.

Though Rosemary has been leading hikes for Pocono Outdoor Club for years, neither of us had been here before. A kiosk displays the trail map and lists some of the natives: black bears, river otters, snowshoe hares, and a profusion of nesting and migratory birds. The trail is clearly marked from the trailhead and soon becomes a narrow boardwalk. This is a taste of what is to come: in this boggy place, the earth is often spongy and wet, even on “solid” ground.

Blue blazes show the way. The path is covered with wet leaves, and often spiked with slate shards. We find lovely conglomerate rocks, pebbled with nuggets of quartz. Ten thousand years ago, as the ice sheet that scraped and shaped this landscape retreated, it also dropped the huge boulders that we see among the trees. We cross tangled, surface-running roots of big birches, and note pitch pine, balsam fir and tamarack along the trail.

Before long, the trail meets Two-Mile Run. We follow its burbling, fast-running waters upstream, where the woods suddenly open and light floods the wide, flat marsh ahead. Long, low rays of sun pick out a landscape of winter watercolors — plum and pink, grey, black-green, pale buff and amber, spiked with sumac-red and orange.

A long boardwalk leads us through the heart of all this beauty. Sphagnum moss is everywhere. We see shrubs like winterberry, witch hazel and blueberry and groves of slim white birches. Animal paths crisscross the boggy ground. The marsh is ringed by one of Pennsylvania’s largest forests of native black spruce.

Hunters are active here, so we are both wearing blaze orange and are not surprised to see tree stands and wildlife blinds along the way. As we leave the marsh and begin to loop back toward the starting point, the preserve boundaries run close to private land. Sections of split-rail fence have been placed carefully to help visitors keep to the public trail. A power line cut marks the end of the trail, and a short walk along the fire road brings us back to our cars.

From this natural, glacial reservoir of groundwater at the top of Pocono Plateau, the waters of Two-Mile Run begin their long journey: flowing to Tobyhanna Creek, and then to the Lehigh River, on the way to Easton, the Delaware River and the Atlantic Ocean.

Rare plants. Ancient waters. A landscape laid down in deep time. But truly unique? Ask Bud Cook, who has been protecting special places at The Nature Conservancy for decades: “Nowhere else on the planet,” Bud says, “is there anything like this place.”

Why not come see for yourself?

Carol Hillestad is a hike leader and writer for Get Outdoors Poconos, a grant-funded series administered by Brodhead Watershed Association.