The Mediumwave transmitter Lopik is a medium wave broadcasting facility near Lopik in the Netherlands. It works on 675 kHz and uses as aerial a 196 metre high guyed steel framework mast, which was built in 1938 and which is insulated against ground. Until April 21, 2004 there was a smaller guyed steel framework mast for the mediumwave frequency 1332 kHz.
This mast should not be confused with the nearby Gerbrandy tower, which is used for FM- and TV-broadcasting. The Gerbrandy Tower used to be in the community of Lopik as well before an administrative change, and is often referred to as the "Lopik tower".