West Texas is a loosely defined part of the U.S. state of Texas, generally encompassing the arid and semi-arid lands west of a line drawn between the cities of Wichita Falls, Abilene, and Del Rio. No consensus exists on the boundary between East Texas and West Texas. While most Texans understand these terms, no boundaries are officially recognized and any two individuals are likely to describe the boundaries of these regions differently. Walter Prescott Webb, American historian and geographer, suggested that the 98th meridian separates East and West Texas; Texas writer A.C. Greene proposed that West Texas extends west of the Brazos River. Use of a single line, though, seems to preclude the use of other separators, such as an area - Central Texas.