From The Columbia Encyclopedia
largest state in the coterminous United States. It is located in the south-central part of the country and is bounded by Oklahoma, across the Red River except in the Texas panhandle (N); Arkansas (NE); Louisiana, across the Sabine River (E); the Gulf of Mexico (SE); Mexico, across the Rio Grande (SW); and New Mexico (W). Texas is roughly spade shaped. The vast expanse of the state contains great regional differences and can be broken down into subregions: East Texas, Gulf Coast, Rio Grande Valley, Blackland Prairies, High Plains, and West Texas.