Old Tunnel State Park was acquired by the Texas Parks and Wildlife Department (TPWD) in 1991. In 2012, Old Tunnel was transferred to the State Parks Division. Due to the amount of visitation to the site, the Executive Committee determined that operations could be better served through the Parks Division. Although Old Tunnel will now be operated as a state park, the Wildlife Division will maintain some management oversight of the area in compliance with U.S. Fish and Wildlife grant stipulations. Research has been conducted at Old Tunnel WMA since the property was purchased by TPWD, and results of these research projects have allowed biologists to make sound management decisions. Research will continue to be conducted under the Parks Division. Bat-viewing opportunities exist seven nights a week and educational presentations are given Thursday through Sunday, May through October.
The historical marker at the top of the hill outlines the building of the Old Tunnel. The Fredericksburg Historical Society provided the marker to the area. A kiosk located at the upper viewing area provides information about the bats at this location, bats in general, and a brief description of the policies and procedures of the state park. An additional kiosk, located at the lower viewing area, provides a brief history of the tunnel, as well as additional information on Mexican free-tailed bats and other bats of the world.