Jesberg

Jesberg lies from 210 to 675 m high in the Gilsa river valley eastsoutheast of the Wüstegarten, which at 675 m above sea level is both the Kellerwald range's and the Schwalm-Eder district's highest peak. The community can be reached by Federal Highway B 3.
The Burg Jesberg, a castle built by the noble family of Linsingen in 1241, was later sold to the Archbishopric of Mainz, and along with Naumburg and Fritzlar was one of the Archbishops' main bases in the struggle against the Landgraves of Hesse. In 1723, the Prinzessingarten — Princess's Garden — near Jesberg was built in what is now the Jesberg State Forest. It can still be seen, along with its centrepiece, the Prinzessingarten-Eiche, a big oaktree, although nowadays, little of the actual garden is still preserved.

Wikipedia