The Gloriette in Schloss Schönbrunn is the biggest Gloriette that was ever made. It was built in 1775 under the Emperess Maria Theresia and was used as a dining and ball room as well as a breakfast room for the Emperor, to enjoy the view over the city of Vienna. Since 1996 there's a Café in the Gloriette.
https://en.wikipedia.org/wiki/Gloriette