Which monument in Oberndorf bei Salzburg is dedicated to a Christmas carol that Franz Xaver Gruber is best known for composing? 
Silent-Night-Chapel: The Silent Night Chapel (Stille-Nacht-Kapelle) is located in the town Oberndorf bei Salzburg in the Austrian province of Salzburg and is a monument to the Christmas carol "Silent Night" and its librettist, Joseph Mohr and composer, Franz Xaver Gruber.
i don't know