 As the freeway passes from the Rocky Mountains to the Great Plains , I @-@ 70 enters the Denver metropolitan area , part of a larger urban area called the Front Range Urban Corridor . The freeway arcs around the northern edge of the LoDo district , the common name of the lower downtown area of Denver . Through the downtown area , US 40 is routed along Colfax Avenue , which served as the primary east – west artery through the Denver area before the construction of I @-@ 70 . Through downtown , US 6 is routed along 6th Avenue before departing the I @-@ 70 corridor to join Interstate 76 on a northeast course toward Nebraska . The freeway meets Interstate 25 in an interchange frequently called the Mousetrap . From I @-@ 25 on to I @-@ 225 , I @-@ 70 serves — together with those two Interstates — as part of an inner beltway around Denver . 
