The rocks in Gerums­ber­get are the same as in the other tab­le mountains (base­ment, sand­sto­ne, alum sha­le, limesto­ne, clay sha­le, and dole­ri­te), but the mountain is part of the same limesto­ne pla­teau as Varvs­ber­get and Plan­ta­ber­get. The actu­al visib­le mountain thus con­si­sts only of clay sha­le and dole­ri­te. The name Gerums­ber­get is very old, found in writ­ten sour­ces dating back to the 14th cen­tu­ry. The mountain is situ­a­ted between the muni­ci­pa­li­ti­es of Fal­kö­ping and Tida­holm, and reaches a height of 326 metres abo­ve sea level.

Seve­ral archae­o­lo­gi­cal finds have been disco­ve­red in a bog (Hjor­ta­mos­sen) atop the mountain, inclu­ding a wool clo­ak, an oar, and a fishing net.

Natu­re reser­ves on Gerumsberget