▁about ▁ 9 0 ▁kilom eters , ▁of ▁which ▁about ▁ 7 0 ▁kilom eters ▁are ▁navig able ▁water way . ▁The ▁longest ▁trib ut ary ▁in ▁the ▁region ▁is ▁the ▁Fil s ▁( 5 0   km ), ▁followed ▁by ▁M urr ▁( 4 5   km ), ▁the ▁R ems ▁( 3 5   km ) ▁and ▁the ▁En z ▁( 3 0   km ). ▁ ▁Top ograph ically ▁the ▁Region ▁l ays ▁between ▁ 1 7 0 ▁m ▁above ▁sea ▁level ▁( Ne ck ar ▁near ▁Kirch heim ▁am ▁Ne ck ar ) ▁and ▁ 8 3 5 ▁m ▁above ▁sea ▁level ▁( sw ab ian ▁al bs ▁plate au ▁near ▁H ohen stadt ). ▁ ▁Dem ograph ics ▁ ▁About ▁ 2 . 7 ▁Mill ion ▁people ▁live ▁in ▁the ▁Stuttgart ▁Region , ▁which ▁corresponds ▁to ▁a ▁quarter ▁of ▁the ▁entire ▁population ▁of ▁Baden - W ür ttemberg ▁at ▁about ▁on ▁t enth ▁of ▁its ▁size . ▁ 7 4 9 ▁people / km ² ▁is ▁the ▁regions ▁average ▁population ▁density . ▁ ▁The ▁numbers ▁of ▁inhabitants ▁are ▁census ▁results ▁( ¹ ) ▁or ▁official ▁updates ▁of ▁the ▁statistical ▁state ▁office ▁of ▁Baden - W ür ttemberg ▁( only ▁primary ▁residence ). ▁ ▁Ver band ▁Region ▁Stuttgart ▁ ▁The ▁Ver band ▁Region ▁Stuttgart ▁( V RS ) ▁a ▁public ▁body , ▁is ▁as ▁one ▁of ▁ 1 2 ▁regional ▁associations ▁in ▁Baden - W ür ttemberg ▁political ▁and ▁administrative ▁instance ▁of ▁the ▁Stuttgart ▁Region . ▁Its ▁prede cess