Most parts of the state of Texas are quite flat.
But in a part of West Texas called the Trans-Pecos region, west of the Pecos River, the terrain is mountainous.
In fact, eight mountains in the Guadalupe range have elevations of more than 8,000 feet (2,438 m) above sea level.
The shortest river in Texas is the Comal River, at only 2.5 miles (4 km) long.
Crystal clear, the Comal originates from a spring in the central Texas town of New Braunfels and empties into the Guadalupe River in that same town.