- west ▁to ▁south - east ▁orient ed ▁cra cks ▁appeared ▁in ▁the ▁rock , ▁which ▁rivers ▁transformed ▁into ▁the ▁valle ys ▁still ▁present ▁in ▁the ▁landscape , ▁for ▁example ▁the ▁la kes ▁L ång s jön , ▁Mag el ungen , ▁and ▁D rev v iken . ▁ ▁All ▁around ▁Stockholm , ▁such ▁open ▁fields ▁are ▁separated ▁by ▁forest - lad en ▁rid ges . ▁ ▁Late ▁in ▁this ▁ge ological ▁process , ▁east ▁to ▁west - orient ed ▁fault s ▁appeared , ▁resulting ▁in ▁for ▁example ▁the ▁tall , ▁dark ▁cl iffs ▁along ▁the ▁northern ▁water front ▁of ▁S öder mal m . ▁ ▁Three ▁million ▁years ▁ago , ▁a ▁series ▁of ▁ice ▁ages ▁started ▁to ▁gr ind ▁down ▁the ▁north - bound ▁fault s , ▁leaving ▁the ▁south - bound ▁form ations ▁int act . ▁ ▁During ▁the ▁latest ▁ice ▁age ▁( 7 0 , 0 0 0 - 9 , 5 0 0 ▁B CE ), ▁the ▁area ▁surrounding ▁Stockholm ▁was ▁covered ▁by ▁an ▁ice ▁layer ▁up ▁to ▁two ▁kilometres ▁thick . ▁ ▁While ▁the ▁ice ▁effectively ▁elimin ated ▁every ▁trace ▁of ▁pre - ice ▁age ▁life , ▁it ▁is ▁assumed ▁humans ▁probably ▁did ▁inhab it ▁the ▁area ▁before ▁the ▁ice ▁age , ▁not with standing ▁no ▁arch ae ological ▁traces ▁can ▁confirm ▁it . ▁ ▁Nevertheless , ▁b ones ▁from ▁a ▁m amm oth ▁have ▁been ▁found ▁in ▁the ▁Brun ke berg s å sen ▁es ker ▁stretch ing ▁north ▁to ▁south ▁through ▁central ▁Stockholm . ▁ ▁As