▁the ▁Den ver ▁metropol itan ▁area , ▁part ▁of ▁a ▁larger ▁urban ▁area ▁called ▁the ▁Front ▁Range ▁Urban ▁Cor rid or . ▁The ▁fre ew ay ▁ar cs ▁around ▁the ▁northern ▁edge ▁of ▁the ▁Lo Do ▁district , ▁the ▁common ▁name ▁of ▁the ▁lower ▁dow nt own ▁area ▁of ▁Den ver . ▁Through ▁the ▁dow nt own ▁area , ▁US   4 0 ▁is ▁rout ed ▁along ▁Col f ax ▁Avenue , ▁which ▁served ▁as ▁the ▁primary ▁east – west ▁ar tery ▁through ▁the ▁Den ver ▁area ▁before ▁the ▁construction ▁of ▁I - 7 0 . ▁Through ▁dow nt own , ▁US   6 ▁is ▁rout ed ▁along ▁ 6 th ▁Avenue ▁before ▁depart ing ▁the ▁I - 7 0 ▁cor rid or ▁to ▁join ▁Inter state   7 6 ▁on ▁a ▁n ortheast ▁course ▁toward ▁Neb r aska . ▁The ▁fre ew ay ▁meets ▁Inter state   2 5 ▁in ▁an ▁inter change ▁frequently ▁called ▁the ▁M ous et rap . ▁From ▁I - 2 5 ▁on ▁to ▁I - 2 2 5 , ▁I - 7 0 ▁serves — t ogether ▁with ▁those ▁two ▁Inter states — as ▁part ▁of ▁an ▁inner ▁bel t way ▁around ▁Den ver . ▁ ▁I - 7 0 ▁has ▁one ▁official ▁branch ▁in ▁Colorado , ▁Inter state   2 7 0 , ▁which ▁connect s ▁the ▁inter state ▁with ▁the ▁Den ver – B ould er ▁Turn pi ke . ▁Where ▁these ▁two ▁fre ew ays ▁merge ▁is ▁the ▁bus iest ▁portion ▁of ▁I -