The Internet does not disappoint. Random curiosity left me wondering about the origin of the tunnel painted on the wall gag.
It was the first Warner Bros. Looney Tunes cartoon to feature Road Runner and Wile E. Coyote, Fast and Furry-ous, released September 17, 1949.
Now you know.
Shout out to musical direction by the great Carl Stalling.
Meep, meep!
Vimeo
Fast and Furry-ous (1949)