Lubbock is a city located in the northwestern part of Texas. The region is historically known as the Llano Estacado. Lubbock is the home of Texas Tech University, and is the11th largest city in Texas. Lubbock's nickname is the "Hub City" which essentially comes from being the education, economic and health care center of a multi-county region generally referred to as the South Plains. Lubbock is the largest continuing cotton-growing region in the world and is majorly dependent on irrigation water taken from Texas's Ogallala Aquifer.