Hardberg, Mountain summit in Odenwald, Germany.

Hardberg is a mountain summit in the Odenwald of Hesse, reaching approximately 593 meters in elevation. A tall transmission tower stands at the peak, making it a visible landmark across the forested landscape.

The 135-metre lattice tower of the Hardberg transmitter was erected in 1988 and carries Hessischer Rundfunk's VHF radio and directional radio equipment. Until October 2008 a psychotherapeutic clinic stood at about 530 metres on the northern spur; since 2010 its building has housed the Siedelsbrunn Buddhist monastery. A 900-metre ski slope with lift on the northeast slope was dismantled in the 1980s.

The name Hardberg refers to the hard, crystalline rock of the western slope, which borders the red sandstone to the east. On the northeastern slope at about 505 m lies the hamlet of Siedelsbrunn, and since 2010 the former Hardberg clinic building there has housed a Buddhist monastery.

The summit ridge runs north to south for nearly 1 km, with the Stiefelhöhe (584 m) continuing the same woodland to the south. The 135 m transmitter tower occupies the northern part of the summit area, so the open ground around it is the easiest orientation point. The former Hardberg ski slope on the northeast flank, served by a lift, was dismantled in the 1980s.

The 135-metre lattice tower of the Hardberg transmitter, built in 1988, weighs 130 tons and stands on a base of just 12 by 12 metres. It carries FM radio and directional radio antennas for the Hessischer Rundfunk. The tower occupies the northern part of the summit ridge.