Old Tunnel State Park

Texas hill country Region

Old Tunnel State Park is home to up to 3 million Mexican free-tailed bats and 1,000 to 3,000 cave myotis bats from May to October. This 920-foot, abandoned Fredericksburg and Northern Railway railroad tunnel was purchased by Texas Parks and Wildlife Department for the specific purpose of protection and management of the bats. The bat colony at Old Tunnel State Park is considered a pseudo-maternity colony. While pregnant and lactating females use the tunnel, pups are not born in the tunnel but in nearby caves or bridges with more stable temperature and humidity levels. Because of this, the size of the colony fluctuates greatly throughout the season. In June, the population of bats can be smaller, after the females leave to give birth. However, by early August, females and juveniles will return to Old Tunnel and the colony size will continue to increase through mid-August. The largest population of bats can be seen during the months of August and September. The bats will usually begin migrating back to Mexico in late October. The state park also offers a 1.5-mile nature trail through woodlands of live oak, escarpment black cherry, black walnut, hackberry, and Ashe juniper. Birds along the trail include yellow-billed cuckoo, Carolina wren, Carolina chickadee, and painted bunting. Several species of raptors can also be seen soaring over the adjacent canyon.

Visitation Info

View Old Tunnel State Park fees, reservations, and hours information.

ADA Accessible

Yes

Ownership

Texas Parks and Wildlife Department

Contact Information

Multimedia

  • Bats flying Old Tunnel State Park. Photo: Stephanie Lee Shelton.
  • Bats emerge at Old Tunnel State Park. Photo: TPWD.
  • Overlooking the old railway tunnel-turned bat cave. Photo: TPWD.
  • Batwatching Basics - Tips from a Wildlife Biologist. Video: TPWD.
  • Bats are reviled by some, and treasured by others. The more we learn about bats the more we appreciate them. Follow some scientists as they study the economic impact of bats through the use of radio telemetry and thermal imaging. Video: TPWD.

Location & Directions

From Fredericksburg, take US 290 east to Old San Antonio Road (OSR), about 0.5 mile east of the Fredericksburg city limits. Turn right on OSR and drive 10.5 miles to the parking lot at Old Tunnel State Park, which will be on the left. From IH-10 in Comfort, take Exit #523 (Hwy. 87 North). Turn south, heading into the town of Comfort. Go 0.5 mile to the stop light (look for sign with “Old Tunnel State Park”), and turn left at the stop light onto FM 473. Stay on FM 473, which will take you back underneath IH-10, for 5 miles. When FM 473 makes a right turn to Sisterdale, go straight ahead on the Old #9 Highway for 8 more miles. Old Tunnel State Park will be on the right at the top of a hill.

Bat Fact

Bats are incredibly long-lived for their size, with the oldest confirmed insectivorous bat living 41 years!