This city's Schönbrunn Palace was the summer residence of rulers like Maria Theresa and Franz Joseph.
This city houses the headquarters of OPEC as well as the International Atomic Energy Agency. In 1857, this city's ancient walls were demolished in favor of a Ringstrasse_,_ now lined by many notable buildings such as the Rathaus, the Hofburg Palace, and the State Opera. This city's St. Stephen's Cathedral features a distinctive tiled roof characterized by its colored zigzag pattern and prominent double-headed eagles. This city's Schönbrunn Palace was the summer residence of rulers like Maria Theresa and Franz Joseph. For 10 points, name this former center of Habsburg power and current capital of Austria.
This city houses the headquarters of OPEC as well as the International Atomic Energy Agency.
{Vienna}