 The Federal Aviation Administration has operated a 25 @-@ foot ( 7 @.@ 6 m ) tall very high frequency omnidirectional range ( VOR ) aviation tower on Upper Table Rock since the 1960s . The tower 's purpose is to broadcast precise coordinates to nearby aircraft to assist in navigation . The facility is closed to the public due to the threat to the safety of the occupants of the aircraft . However , the structure sustained $ 40 @,@ 000 damage in 1997 when vandals unsuccessfully attempted to steal aluminum antennas from the 15 @-@ foot ( 4 @.@ 6 m ) tall fiberglass shell on the roof of the building . 
