Knoxville is located in the Great Appalachian Valley between the Great Smoky Mountains and Cumberland Plateau; it is also ribboned with rivers, making this a very outdoor-oriented town. It is the third largest city in Tennessee. Knoxville is particularly attractive because it is home to the Vols - the University of Tennessee. As such it is a vibrant college town with big-time sports and many cultural events. The 2007 population was 183,000. Knoxville was the site of the 1982 World's Fair and several buildings, including the Sunsphere, were built for that event.