“Adopt-a-Highway” is a program where citizens and businesses can “adopt” a stretch of highway by helping to pay for its care. It’s not like adopting a child, but there are jokes.
 
Greek-American comedian and actor Zach Galifianakis said in the stand-up comedy documentary film The Comedians of Comedy (2005):
 
“At what age do you tell a highway it was adopted?”
 
The line was repeated in his stand-up film Zach Galifianakis: Live at the Purple Onion (2006):
 
“At what age should you tell a highway that it was adopted? I think… around seven. Because that’s when they’re going to start thinking to themselves, ‘I don’t look much like the Kiwanis Club.’”
   
       
Wikiquote: Zach Galifianakis
Zachary Knight “Zach” Galifianakis (born October 1, 1969) is a Greek-American comedian, actor and writer.
 
Live at the Purple Onion (2007)
(...)
At what age do you think it’s appropriate to tell a highway it’s adopted?
     
IMDb (The Internet Movie Database)
The Comedians of Comedy (2005)
R | 1h 43min | Comedy , Documentary | 12 March 2005 (USA)
Director: Michael Blieden
Writers: Maria Bamford, Zach Galifianakis | 2 more credits »
Stars: Patton Oswalt, Brian Posehn, Maria Bamford |
 
6 August 2005, The Morning Call (Allentown, PA), “The Week in Review: The Comedians of Comedy” by Tom Coombe,,” pg. D7, col. 3:
THE COMEDIANS OF COMEDY
The only downside to last Saturday’s Comedians of Comedy show at Philadelphia’s Theatre of Living Arts came afterwards, trying to decide which of the four stand-up comics—Patton Oswalt, Maria Bamford, Zach Galifianakis or Brian Posehn—was funniest.
(...)
In a pinch, Galifianakis (“I hope I’m pronouncing that right,” he said) would probably be a good bet for the star of the show, playing the piano as he let off a stream of absurdity (and thankfully, mostly printable) one-liners: “At what age do you tell a highway it was adopted?”
     
11 November 2005, Los Angeles (CA) Times, “TV Review: ‘The Comedians of Comedy’” by Paul Brownfield, pg. E30:
“The Comedians of Comedy,” debuting at 11 tonight, features four comics—Patton Oswalt, Brian Posehn, Maria Bamford and Zach Galifianakis—on the road, touring the East Coast in a bus.
(...)
We get snippets of their performances (“At what age do you tell a highway it was adopted?” goes one of Galifianakis’ setups), ...
       
IMDb (The Internet Movie Database)
Zach Galifianakis: Live at the Purple Onion (2006 Video)
Quotes
Zach Galifianakis: At what age should you tell a highway that it was adopted? I think… around seven. Because that’s when they’re going to start thinking to themselves, “I don’t look much like the Kiwanis Club.”
 
Twitter
Brian Smith
@HomelessBrian
At what age do you tell a highway it is adopted?
9:06 AM - 8 Aug 2007
 
Reddit—Funny
I’ve always wondered… (self.funny)
submitted August 18, 2011 by dmelnyczuk
at what age do you tell a highway it’s adopted?
     
Reddit—AskReddit
What is the funniest one-liner you’ve heard?
(self.AskReddit)
submitted August 24, 2012 by atmarcotte2
Since I get to start, I’m going to be a rebel and post two:
“At what age do you think it’s appropriate to tell a highway it’s adopted?” - Zach Galifianakis
   
Google Books
The Profound Ramblings of a Brilliantly Deranged Mind
By Charlie Petteway
BookRix
2017
Pg. ?:
At what age do you tell a highway it was adopted?
 
Reddit—Oneliners
What age is it appropriate to tell a highway they’re adopted?
submitted September 26, 2018 by dontreadmycommemt