The Big Thicket reaches Jasper County along the Neches

Jasper County's Big Thicket connection is easiest to understand from the Neches River. The Upper Neches River Corridor Unit runs 34 miles through Jasper and Tyler counties, starting below B.A. Steinhagen Lake at Town Bluff Dam and flowing south toward the Neches Bottom and Jack Gore Baygall Unit. That makes the river edge part of the preserve, not just a pretty boundary line on the county map.

The lower unit is rugged rather than arranged like a developed park. It covers 13,735 acres in Hardin and Jasper counties, with oxbow lakes, paddling, fishing, hunting in season, and backcountry camping. There are no facilities or maintained trails inside the unit, and hiking is off-trail.

McQueens Landing on County Road 150 gives access to the Upper Neches corridor south of Steinhagen Lake, while the lower Neches corridor includes the Evadale boat ramp on U.S. 96. Private land exists in some spots along the waterways: purple paint marks private property, while yellow paint or white boundary signs mark public land. From McQueens Landing toward Evadale, part of Jasper County's western edge is also a national preserve corridor.