Big Slough Trail is a 1.2 mile moderately trafficked loop trail located near Freeport, TX that features a river. The trail is good for all skill levels and primarily used for hiking, walking, and birding. Dogs are also able to use this trail.
We went in January. The weather was gloomy and the trail's only real issue at that time of year were the huge ant mounds. I was thankful I wore proper hiking boots, because the mud was serious, and I imagine it's only worse in summer. The trail starts out with a boardwalk, from which we were able to see a smaller, wild alligator. Apparently a lot more show their faces at different times of the year. We also decided to get out and walk a lot of the tour that is meant to be done inside your vehicle. There were a lot of great birding opportunities, if you're into that sort of thing. Wouldn't recommend for people who hike for adventure's sake, though.
The hiking is nothing exciting and maybe a bit scary depending on when you go. I went the first week of October 2014. It was a gorgeous day. I had a great time visiting the entire refuge. The Big Slough Trail was a bit scary. I ran across a family of wild hogs. I also encountered numerous large spider webs of huge (bigger than I've ever seen) banana spiders. I had to duck under these webs to proceed through the trail at least 5 times. Between the hogs and spiders, it was NOT a leisurely walk. Also, the trail apparently isn't a frequently traveled path as there is no "beaten path" and is more of a mowed path. They have another trail I didn't get to walk because they hadn't mowed it. The rest of the park (motor trail) is great and very interesting.