The Sharp 's Ridge collection of broadcast towers , commonly referred to as an " antenna farm " is a good example of radio and TV stations , co-locating their broadcast towers near each other on the highest point near their FCC city of license . The nearest " antenna farms " to Sharp 's Ridge are on Holston Mountain in upper East Tennessee , home to most of the FM and TV stations in the Tri-Cities ( Bristol , Virginia-Kingsport , Tennessee-Johnson City , Tennessee ) Designated Market Area ( DMA ) , and the Signal Mountain broadcast antenna farm , near Chattanooga , Tennessee , home to most of the FM and TV station antennas in that DMA . Although most radio and TV stations are in fierce competition with each other in their broadcast markets , they will often locate their broadcasting antennas very near each other , and in some cases , will even share land or towers with each other , in the interests of space , land availability , and the cost of putting a transmission building on top of a mountain . Other examples of co-located towers on mountain peaks in the United States are on Poor Mountain near Roanoke , Virginia ; Red Mountain in Birmingham , Alabama ; Mount Wilson near Los Angeles ; Sutro Tower in San Francisco ; Lookout Mountain , Colorado near Denver ; Cedar Hill between Dallas and Fort Worth ; South Mountain Park near Phoenix ; Nelson Peak near Salt Lake City ; Sandia Crest near Albuquerque , New Mexico ; and probably the most famous broadcast antenna farm of all : The World Trade Center Tower One , on which all of the New York City television and FM stations had their antennas . All were lost when Twin Towers One and Two collapsed after the September 11 attacks in 2001 . Those antennas now broadcast from their old home , 200 feet lower , on the Empire State Building
September 11 attacks
September 11 attacks
Sharp's Ridge