Knoxville lies on the Tennessee River in the eastern part of the US state of the same name. The 81-meter Sunsphere – i.e. a high observation tower topped with a distinctive, golden ball is one of the best-known structures in the city. It was built for the World's Fair organized by the city in 1982. Among other high buildings rising above Knoxville there are a 100-meter First Tennessee Plaza office building, Riverview Tower and Andrew Johnson Building. In Knoxville there is also the so-called "Body Farm", which is the place where research is conducted on corpses in various stages of decomposition.