The KVLY-TV mast (formerly the KTHI-TV mast) is a television transmitting tower in North Dakota, and at 2063' (628m) it is the tallest man-made structure in the world.
Located three miles west of Blanchard, North Dakota (at 47° 20' 32" N, 97° 17' 20" W), it became the tallest artificial structure upon the completion of its construction on August 13, 1963. It was surpassed by 18m (57 feet) in 1974 by the Warszawa radio mast near Konstantynow, Poland, which collapsed on August 10, 1991, making the KVLY mast again the tallest.
The tower was built by Hamilton Directors and Kline Iron and Steel, and took thirty days to complete, at a cost of a half million dollars.
Owned by the Meyer Broadcasting Company of Bismarck, the tower broadcasts at 316kW for television station KVLY (channel 11, an NBC affiliate) which is based in Fargo. The tower provides a broadcast area of roughly 30,000 square miles (77,700 km2).
Its overall height above mean sea level is 926m (3,038 ft). Some time after its completion, the Federal Aviation Administration imposed a limit of 2063', based on this tower's height, on future construction; consequently no taller structures may legally be built in the U.S. at the current time.
The call letters of the television station for which it was built were originally KTHI, the "HI" referring to the height of the mast. The top is reachable by service elevator or ladder.