The Haselstein castle ruins are located to the west of Haselstein. It dates back to the 11th century and has been in ruins since the 16th century. 

Summit castle from the 11th century

A summit castle once stood enthroned on a rugged rock near Haselstein. Haselstein Castle was probably built in the 11th century near the existing village. Haselstein was first mentioned in 780/81 in connection with the border areas of the Rasdorf monastery. The oldest written evidence of the castle dates back to 1113, and a few years later there is also mention of its inhabitants, the Lords of Haselstein. Haselstein evidently became more important in the 12th century - the Fulda monastery had the castle extended. Its owners were first described as knights in 1135. In 1160, Fulda Abbot Markward I founded a village at the foot of the castle and granted it market rights.

Decay since the 16th century

During the Middle Ages, numerous noble families and the provosts of Michaelsberg and Johannesberg appear as owners or castellans - many of them were Rhön noble families such as the von Buchenau, von Buttlar and von Hasel families. At the beginning of the 14th century, after the extinction of the von Haselstein family, the castle fell to Fulda Abbey. It became the seat of a new office, which united the villages of Rasdorf and Soisdorf. At the beginning of the 19th century, the property was secularized and initially fell to Prince William of Orange. The castle no longer existed at this time - it had been in ruins since the 16th century. Today, only a few, difficult to identify remains of the walls remain.

The ruins are located on the premium hiking trail Extra tour "Ulmenstein".