Sender Olsberg, Communication tower in Olsberg, Germany.

Sender Olsberg is a 58-metre freestanding steel tube tower on the southern summit of the Olsberg mountain, about 430 metres south-southeast of the 703.8-metre north summit. Its tubular section measures 2.20 metres in diameter at the base and 1.60 metres at the top, and it weighs 50 tonnes. It carries FM and DAB antennas but no television equipment.

The tower was built in 1984 by West German Broadcasting to fill radio reception gaps in northern Sauerland and the upper Ruhr Valley. It was constructed to improve radio coverage in this mountainous and sparsely populated region.

The tower carries WDR radio for the northern Sauerland and upper Ruhr valley, but WDR 3 is deliberately not broadcast from here. Its FM programmes arrive by off-air relay from the Teutoburger Wald and Nordhelle transmitters, and since 29 August 2012 digital radio has run on DAB channel 11D instead of 12D.

The tower sits on a mountain ridge at about 700 meters elevation surrounded by extensive forest. The location offers good conditions for hiking and exploring the surrounding Sauerland landscape.

The tower weighs about 50 tons and operates within a single-frequency network that receives programs from other transmitters in the region. The tapered tubular design with reducing diameters toward the top is an efficient construction method for radio transmission in mountainous terrain.