Smallest state park in Texas. Park features an historical railroad tunnel that is home to approximately 2 to 3 million bats. Visitors can access the short nature trail each day from sunrise until 5 p.m. Entrance to the park is free. Bats roost in the tunnel from May through October. During these months, nightly viewing of the bat emergence is available from the upper viewing area for free. Lower viewing area is only open on Thursday through Sunday evenings for $5 per person fee regardless of age. Rules for Old Tunnel State Park: No pets, no smoking on trails or in viewing areas, no alcoholic beverages, no camping, no open fires. For more detailed information about visitation, please call the number listed or visit the Old Tunnel web page.See more..
