Radio masts and towers

Radio masts and towers are typically tall structures designed to support antennas for telecommunications and broadcasting, including television. There are two main types: guyed and self-supporting structures. They are among the tallest human-made structures. Masts are often named after the broadcasting organizations that originally built them or currently use them.

In the case of a mast radiator or radiating tower, the whole mast or tower is itself the transmitting antenna.

Source: Wikipedia