In the Plaza de Santa Ana is the
Cerveceria Alemana a place where Hemingway went.
As for the sign: Hemingway never drank/came here.
I have always taken this as an inverted joke against the American trail in Madrid.
p.s. I also am a fan of Hemingway, especially: 'FOR Whom the Bell Tolls' but also 'Fiesta' and more so for his nobel prize piece of literature.
[This message has been edited by steveaqui (edited 10-06-2000).]