HARLEYVILLE — The secluded boardwalk curves under 1,000-year-old cypress trees on the way into the heart of Four Holes Swamp. And visitors soon will be able to walk its full length again.

For now, they’re still diverted in the uplands to a wooded trail for several hundred feet while the boardwalk gets worked on. But at least that’s better than it was — heavy rains in August washed out a walkway along that trail.

The 18,000-acre Audubon Center and Sanctuary sits out all by itself, away from a major road, down in the thick bottoms of what might be the largest remaining virgin cypress-tupelo swamp forest in the world.

The nearly 2-mile-long boardwalk is its centerpiece. The August rains put the detour trail underwater and virtually off limits until the rains receded. But it’s now back in business.

“We are currently still running with visitors needing to drop off the boardwalk and walk (the) trail before coming back up onto the boardwalk past the construction zone. Hopefully, in about two weeks this will become unnecessary,” said Mike Dawson, center director.

Four Holes Swamp runs from the Midlands into the Edisto River, the largest free-flowing blackwater river in the world.

The sanctuary is owned and managed by the National Audubon Society at Four Holes Swamp. The center charges an $8 admission, $4 children to enter the forest. For more information, http://beidlerforest.audubon.org or 843-462-2150.

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