Big Bend Ranch State Park-Texas Parks and Wildlife: “It’s a good day for a drive.” That’s what our park rangers are likely to recommend now through the end of August. Today’s high in Presidio is 110 degrees, which means portions of the park along River Road (FM 170) will reach 120+. We strongly encourage visitors to be off trail and in air conditioning by 11 a.m., but the earlier the better. The good news is that River Road (Presidio to Lajitas) was named one of the Top 10 Scenic Highways in the U.S. by @natgeo. If you want to take a scenic drive, Big Bend Ranch State Park is a good place to be. Please recreate responsibly and grab a park map before you head out on River Road. Cell signal is non-existent on the 51-mile stretch between Presidio and Lajitas.