Three interstate highways—I-35 to the west (Dallas–Fort Worth to San Antonio, with Austin in between), I-45 to the east (Dallas to Houston), and I-10 to the south (San Antonio to Houston) define the Texas Urban Triangle region. The region of contains most of the state's largest cities and metropolitan areas as well as 17 million people, nearly 75 percent of Texas's total population. Houston and Dallas have been recognized as beta world cities. These cities are spread out amongst the state. Texas has 254 counties, which is more than any other state by 95 (Georgia).