Anthorn VLF transmitter

The Anthorn VLF transmitter is a very low frequency (VLF) transmitter near Anthorn, Cumbria, used primarily for transmitting orders to submarines on 19.6 kHz. Its callsign is GBZ.

The transmitter is a NATO facility, controlled from Northwood Headquarters along with three other VLF transmitters in Norway, Germany, and Italy.[1]

The characteristic triangular pattern of roads clearly visible on the aerial photograph indicates that this was a World War II military airfield, in this case operated by the Royal Navy Air Service as HMS Nuthatch. The transmitter is now operated by VT Communications.