Dominating the square is Saint Stephen's Cathedral, which the Viennese affectionately call the Steffl. Its most recognizable feature is undoubtedly the roof, covered in exactly 230,000 glazed tiles. If you look closely, you will see the double-headed eagle, the symbol of the Habsburg Empire, and the coat of arms of the city of Vienna. The roof is so steep—at an angle of 80 degrees—that rain naturally washes the tiles clean and snow almost never settles on it. The south tower you see reaching for the heavens stands at 136 meters tall, and for a long time, no other building in the city was allowed to be taller. Here is a practical tip for those with plenty of energy: you can climb the 343 narrow steps of the south tower for the most breathtaking view of the city's red rooftops and hills. If you prefer a shorter trip, a north tower elevator can take you to the massive twenty-one-ton Pummerin bell, which only rings on the most special occasions.