Quitman Canyon so named for the Quitman Mountains in which it lies is a good collecting location for several species of snakes. The mountains are so named for Fort Quitman that was built in the 1800's in this area. The Fort was occupied by the U.S. Cavalry until the early 1900's. Today, the road running through this canyon is about 18 miles of desolate road. 95% of the time, it is passable by 2-wheel drive vehicle. Only after HEAVY rains is it impassable by 2-wheel drive. The road is fairly rough but I have driven it several times in a two wheel drive Chevrolet pick-up with no hint of trouble. Several locals regularly drive through the canyon in sedans such as Grand Prix's, Nissan Sentra's and other cars of this type.
The above picture is from Quitman Canyon and is characteristic of the fragmented rock found there. There is approximately 10 miles of this type of habitat on the drive through the canyon. The picture below represents the other eight (8) miles of the canyon.
I have personally found every species of snake listed on the main page in this 18 mile stretch of road including Rock Rattle Snakes, Texas Lyre Snakes (protected) and Trans-Pecos Rat Snakes. I have been told that there have been Alterna found here but as of yet, I have found none. The dirt road through this canyon starts about 5 miles South of Sierra Blanca, Texas and runs about 18 miles until it connects with pavement again just North of the Rio Grande River. To get to this area drive straight South from Sierra Blanca, Texas on farm road 1111 until you arrive at the dirt road. At the "Y" stay to your right and don't deviate from the main road. Remember, only the road is public and the land surrounding it is private. Although the road through the canyon should be safe, I don't recommend collecting on the river at night as there is a sometimes violent group that frequents the area on the Mexican side of the river. Snakes start moving in this area around the middle to end of March. The thumbnail below is of a car on the side of Quitman Canyon Rd. about 9 miles North of the Rio Grande River, click to enlarge.