"Donde esta la biblioteca" is a phrase in Spanish, (properly rendered as "¿Dónde está la biblioteca?"), that is a stereotypical and parodied example of something an English speaker would learn in Spanish. Meaning "Where is the library?", it is something that might be found in either a textbook or a guidebook to introduce people to Spanish grammar or pronunciation, or just to give people a useful phrase.
I don't know if there is actually a canonical example of the use of "Donde esta la biblioteca", or, if like the phrase "The real treasure is the friends we made along the way", if it is just a Platonic Ideal that we understand automatically. In 2010, the phrase was used in a song on the television show Community, but it was probably in use long before that.
As a phrase, it would actually be a bad choice to teach beginners, since it is an interrogative, and not declarative, statement; and it also involves the complicated question of ser versus estar. Nevertheless, I still enjoy practicing saying the phrase in the most 101 accent I can manage.
Brevity Quest 2025