Hershey Park runs along a creek and connects technically HWY 6 to the Beltway. There's both paved trails on both sides of the creek and really easy single track that runs along the south side of the creek. You can go further west all the way to Barker Cypress. There's parking by Memorial drive if you take the Eldridge Parkway exit.
One of the things I love about this place is that it's not a dedicated mountain bike park. You can use it to get around Houston. It's there to encourage people to get out and be healthy. It's a model Beaumont should follow.