Wikipedia: Critic Greil Marcus described it as "the most obvious song in the world, and the strangest". Rolling Stone ranked it #274 on their list of the 500 Greatest Songs of All Time.
Origins of the song
As a teenager Richman saw the Velvet Underground perform many times, and the format of “Roadrunner” is derived directly from the Velvets’ song “Sister Ray”. “Roadrunner” mainly uses two chords (D and A, and only two brief uses of E) rather than “Sister Ray”’s three (which are G, F, and C), but they share the same persistent throbbing rhythm, and lyrics which in performance were largely improvised around a central theme.
However, in contrast to Lou Reed’s morally detached saga of debauchery and decay, Richman’s lyrics are passionate and candid, dealing with the freedom of driving alone and the beauty of the modern suburban environment, specifically the suburbs of Boston, Massachusetts. The introductory countoff, "one - two - three - four - five - six!", and lyrics about "going faster miles an hour" with the "radio on" have endeared the song to many critics and listeners since it was first released.
Richman wrote the song by 1970, when he began performing it in public, aged 19. Former bandmate John Felice recalled that as teenagers he and Richman "used to get in the car and just drive up and down Route 128 and the Turnpike. We'd come up over a hill and he’d see the radio towers, the beacons flashing, and he would get almost teary-eyed. He'd see all this beauty in things where other people just wouldn’t see it."