Grim was a giant or a Viking chief who according to the legend lived in one of the caves during summertime. Rest of the year Grim lived on an island in Kalmar sund called Grimskär, just outside the castle in Kalmar (Kalmar Slott).

In the northwest one can see a huge boulder that forms a portal and just behind it one can glimpse  the entrance to the largest cave that is said to have been Grim's habitation.